As used in research, study, and writing, a card file consists of many individual notes with ideas and other short pieces of information that are taken down as they occur or are acquired. The notes may be numbered hierarchically so that new notes may be inserted at the appropriate place, and contain metadata to allow the note-taker to associate notes with each other. For example, notes may contain subject headings or tags that describe key aspects of the note, and they may reference other notes. The numbering, metadata, format, and structure of the notes are subject to variation depending on the specific method employed.
The system not only allows a researcher to store and retrieve information related to their research, but has also long been used to enhance creativity.
The paper slip or card has long been used by individual researchers and by organizations to manage information, including the specialized form of the card catalog.
The first early modern card cabinet was designed by 17th-century English inventor Thomas Harrison (c. 1640s). Harrison's manuscript on the "ark of studies" (Arca studiorum) describes a small cabinet that allows users to excerpt books and file their notes in a specific order by attaching pieces of paper to metal hooks labeled by subject headings. Harrison's system was edited and improved by Vincent Placcius in his well-known handbook on excerpting methods (De arte excerpendi, 1689). The German polymath Gottfried Wilhelm Leibniz (1646–1716) was known to have relied on Harrison's invention in at least one of his research projects.
Later in his own commonplace, under the heading "My way of collecting materials for future writings" (translated), Johann Jacob Moser (1701–1785) described the algorithms with which he filled his card boxes.
Some examples of English-language research manuals with instructions for a card-file note-taking system are: Earle W. Dow's Principles of a Note-system for Historical Studies (1924), Homer C. Hockett's Introduction to Research in American History (1931), Sidney and Beatrice Webb's Methods of Social Study (1932), Carter Alexander's How to Locate Educational Information and Data (four editions from 1935 to 1958), Cecil B. Williams's A Research Manual (three editions from 1940 to 1963), Louis R. Gottschalk's Understanding History (1951), Chauncey Sanders's An Introduction to Research in English Literary History (1952), Jacques Barzun and Henry F. Graff's The Modern Researcher (six editions from 1957 to 2004), and A Guide to Historical Method (three editions from 1969 to 1980) by Robert Jones Shafer and colleagues. A German-language manual on research methods that included instructions for a Zettelkasten was Technique of Scholarly Work (multiple editions from the 1930s to 1970) by Johannes Erich Heyde [de].: 288
One researcher famous for his extensive use of the method was the German sociologist Niklas Luhmann (1927–1998). Starting in 1952–1953, Luhmann built up a Zettelkasten of some 90,000 index cards for his research, and credited it for enabling his extraordinarily prolific writing (including about 50 books and 550 articles). He linked the cards together by assigning each a unique index number based on a branching hierarchy. These index cards were digitized and made available online in 2019. Luhmann described the Zettelkasten as part of his research into systems theory in the essay "Kommunikation mit Zettelkästen".
Moeller, Hans-Bernhard (1989) [1971]. "Perception, Word-Play, and the Printed Page: Arno Schmidt and his Poe Novel". In Matuz, Roger (ed.). Contemporary Literary Criticism: Excerpts from Criticism of the Works of Today's Novelists, Poets, Playwrights, and Other Creative Writers. Vol. 56. Detroit; London: Gale Research. p. 392. ISBN 978-0-8103-4430-3. ISSN 0091-3421. 'Zettel' is German for an index card, and a 'Zettelkasten' is a writer's index card file. Schmidt prepared for Zettels Traum with a collection of more than 100,000 index cards in his legendary card file. 978-0-8103-4430-3
Eco, Umberto (2015) [1977]. "The Work Plan and the Index Cards". How to Write a Thesis. Translated by Caterina Mongiat Farina and Geoff Farina. Cambridge, MA: MIT Press. pp. 107–144. doi:10.7551/mitpress/10029.003.0008. ISBN 978-0-262-52713-2. JSTOR j.ctt17kk9g5.10. OCLC 897401730. A book on the same topic published a decade earlier was: Teitelbaum, Harry (1966). "Note-taking". How to Write Theses: A Guide to the Research Paper. Monarch Notes and Study Guides. Vol. 888–8. New York: Distributed by Monarch Press. pp. 29–39. ISBN 978-0-671-18726-2. OCLC 189085. 978-0-262-52713-2978-0-671-18726-2
Mattern, Shannon (December 2020). "The Spectacle of Data: A Century of Fairs, Fiches, and Fantasies". Theory, Culture & Society. 37 (7–8): 133–155 (146). doi:10.1177/0263276420958052. S2CID 225124110. Over the decades, cards put to personal use have provided aesthetic and intellectual inspiration to myriad artists, writers, and designers. /wiki/Theory,_Culture_%26_Society
Conklin, Jeff (September 1987). "Hypertext: An Introduction and Survey" (PDF). Computer. 20 (9): 17–41. doi:10.1109/MC.1987.1663693. S2CID 9188803. Archived (PDF) from the original on 2017-08-13. One kind of manual hypertext is the traditional use of 3×5 index cards for note taking. Note cards are often referenced to each other, as well as arranged hierarchically (for example, in a shoebox or in rubber-banded bundles). A particular advantage of note cards is that their small size modularizes the notes into small chunks. The user can easily reorganize a set of cards when new information suggests a restructuring of the notes. ... Perhaps the best known version of full hypertext [software] is the NoteCards system developed at Xerox PARC.Neuwirth, Christine; Kaufer, David; Chimera, Rick; Gillespie, Terilyn (November 1987). "The Notes Program: A Hypertext Application for Writing from Source Texts". HYPERTEXT '87: Proceedings of the ACM Conference on Hypertext: November 13–15, Chapel Hill, North Carolina. New York: Association for Computing Machinery. pp. 121–141. doi:10.1145/317426.317437. ISBN 978-0-89791-340-9. OCLC 612420419. The Notes program has an analog in earlier technology: 3×5 note cards. The following section, which outlines some key components in the writing process, lays the theoretical groundwork for exploring the benefits of note cards for writers, the limitations of conventional note cards, and the expected benefits of computer-based note cards. ... At least one of the general network-based editors, NoteCards, could probably be specialized to support the task-optimized linking of the Notes program.Halasz, Frank G. (July 1988). "Reflections on NoteCards: Seven Issues for the Next Generation of Hypermedia Systems". Communications of the ACM. 31 (7): 836–852. doi:10.1145/48511.48514. NoteCards was designed to help people work with ideas. Its intended users are authors, researchers, designers, and other intellectual laborers engaged in analyzing information, constructing models, formulating arguments, designing artifacts, and generally processing ideas. The system provides the user with a network of electronic notecards interconnected by typed links. ... Fileboxes are specialized cards that can be used to organize or categorize large collections of notecards.Lin, Liang-Yi (1989). Learning to Use Hypertext Systems with Metaphors: An Interface Design Perspective (Ed.D. thesis). Urbana, IL: University of Illinois at Urbana-Champaign. ISBN 979-8-207-82289-1. OCLC 23103660. ProQuest 303766704. NoteCards provides the user with a "semantic network" of electronic notecards interconnected by typed links. This network serves as a medium in which the user can represent collections of related ideas. It also functions as a structure for organizing, storing, and retrieving information. In the NoteCards system, a note card is an electronic generalization of the 3 by 5 paper note card. ... Links are used to interconnect individual note cards into networks or structures of related cards. ... The note card metaphor embodied some of the important elements of hypertext systems which the book metaphor did not have.Nielsen, Jakob (1995). "NoteCards (1985)". Multimedia and Hypertext: The Internet and Beyond. Boston: AP Professional. pp. 47–50. ISBN 978-0-12-518408-3. OCLC 31709144. NoteCards may be the most famous of the original hypertext research systems ... Each node is a single notecard ... The links are typed connections between cards. 978-0-89791-340-9979-8-207-82289-1978-0-12-518408-3
Leuf, Bo; Cunningham, Ward (2001). The Wiki Way: Quick Collaboration on the Web. Boston: Addison-Wesley. pp. 15, 365. ISBN 978-0-201-71499-9. OCLC 45715320. Ward called it 'the simplest online database that could possibly work'. In 1994, he wanted a quick way to collaboratively publish software patterns on the Web. Ideas that had developed from his work with program development and HyperCard stacks went into it, and the first 'wiki server' was born. ... Wiki shares some history with the use of index cards in object-oriented programming. Both Wiki and CRC Cards credit an unpublished HyperCard stack as their common ancestor. 978-0-201-71499-9
Alexander, Carter; Burke, Arvid James (1958) [1935]. "Note-taking in Work with Library Materials". How to Locate Educational Information and Data: An Aid to Quick Utilization of the Literature of Education (4th ed.). New York: Teachers College, Columbia University. pp. 168–180. hdl:2027/uc1.b3389054. OCLC 14603864. This book, which was also translated into Spanish, grew out of a pamphlet titled Educational Research first published in 1927. For other editions, see: "Alexander, Carter 1881–1965". WorldCat. Retrieved 16 September 2022. https://hdl.handle.net/2027/uc1.b3389054?urlappend=%3Bseq=190
Alexander, Carter; Burke, Arvid James (1958) [1935]. "Note-taking in Work with Library Materials". How to Locate Educational Information and Data: An Aid to Quick Utilization of the Literature of Education (4th ed.). New York: Teachers College, Columbia University. pp. 168–180. hdl:2027/uc1.b3389054. OCLC 14603864. This book, which was also translated into Spanish, grew out of a pamphlet titled Educational Research first published in 1927. For other editions, see: "Alexander, Carter 1881–1965". WorldCat. Retrieved 16 September 2022. https://hdl.handle.net/2027/uc1.b3389054?urlappend=%3Bseq=190
Haarkötter, Hektor. "'Alles Wesentliche findet sich im Zettelkasten'". heise online (in German). Archived from the original on 2020-07-15. Retrieved 2020-05-31. https://www.heise.de/tp/features/Alles-Wesentliche-findet-sich-im-Zettelkasten-3398418.html
Haarkötter, Hektor. "'Alles Wesentliche findet sich im Zettelkasten'". heise online (in German). Archived from the original on 2020-07-15. Retrieved 2020-05-31. https://www.heise.de/tp/features/Alles-Wesentliche-findet-sich-im-Zettelkasten-3398418.html
Cevolini, Alberto (2016). "Storing Expansions: Openness and Closure in Secondary Memories". In Cevolini, Alberto (ed.). Forgetting Machines: Knowledge Management Evolution in Early Modern Europe. Library of the written word. Vol. 53. Leiden; Boston: Brill. p. 155–187 (158). doi:10.1163/9789004325258_005. ISBN 978-90-04-27846-2. OCLC 951955805. The user may enlarge his collection of extracts, but he can also multiply the number of cross-references, links, and pointers ... Historical research has demonstrated that scholars became aware of this structural feature between the seventeenth and eighteenth centuries. For example, according to Christoph Meiners, the connection of facts and thoughts which are entrusted to a private card file can produce a substantial number of combinations and insights that otherwise might not have existed. 978-90-04-27846-2
Wilken, Rowan (2010). "The card index as creativity machine" (PDF). Culture Machine. 11: 7–30. Retrieved 23 April 2022. https://culturemachine.net/wp-content/uploads/2019/01/373-604-1-PB.pdf
Krajewski, Markus (2011) [2002]. Paper Machines: About Cards & Catalogs, 1548–1929. History and Foundations of Information Science. Vol. 3. Translated by Peter Krapp. Cambridge, MA: The MIT Press. doi:10.7551/mitpress/9780262015899.001.0001. ISBN 978-0-262-01589-9. JSTOR j.ctt5hhmbf. OCLC 698360129. 978-0-262-01589-9
Havens, Earle (2001). Commonplace Books: A History of Manuscripts and Printed Books from Antiquity to the Twentieth Century. New Haven: Beinecke Rare Book & Manuscript Library, Yale University. pp. 34–35. ISBN 978-0-8457-3137-6. OCLC 47767194. 978-0-8457-3137-6
Zedelmaier, Helmut (2016). "Christoph Just Udenius and the German ars excerpendi around 1700: On the Flourishing and Disappearance of a Pedagogical Genre". In Cevolini, Alberto (ed.). Forgetting Machines: Knowledge Management Evolution in Early Modern Europe. Library of the written word. Vol. 53. Leiden; Boston: Brill. p. 102. doi:10.1163/9789004325258_008. ISBN 978-90-04-27846-2. OCLC 951955805. His [Johann Friedrich Blumenbach's] example is the sixteenth-century Swiss naturalist Conrad Gessner, who recommended gluing slips onto bound sheets. 978-90-04-27846-2
Blair, Ann M. (2010). Too Much to Know: Managing Scholarly Information before the Modern Age. New Haven: Yale University Press. doi:10.12987/9780300168495. ISBN 978-0-300-11251-1. JSTOR j.ctt1nptsm. OCLC 601347978. S2CID 187487133. 978-0-300-11251-1
Harrison, Thomas (2017). Cevolini, Alberto (ed.). The Ark of Studies. De diversis artibus. Vol. 102. Turnhout, Belgium: Brepols. ISBN 978-2-503-57523-0. OCLC 1004589834. 978-2-503-57523-0
Blei, Daniela (2017-12-01). "How the Index Card Cataloged the World". The Atlantic. The Atlantic. Archived from the original on 2021-05-08. Retrieved 4 July 2021. https://web.archive.org/web/20210508022255/https://www.theatlantic.com/technology/archive/2017/12/how-the-index-card-catalogued-the-world/547271/
Placcius, Vincent (1689). De arte excerpendi vom gelehrten Buchhalten liber singularis, quo genera & praecepta excerpendi, ab aliis hucusq[ue]; tradita omnia, novis accessionibus aucta, ordinata methodo exhibentur, et suis quaeque materiis applicantur ... (in Latin). Stockholm; Hamburg: Apud Gottfried Liebezeit, bibliop. literisq[ue] Spiringianis. p. 138. OCLC 22260654. /wiki/Vincent_Placcius
Malcolm, Noel (September 2004). "Thomas Harrison and his 'ark of studies': an episode in the history of the organization of knowledge". The Seventeenth Century. 19 (2): 196–232 (220–221). doi:10.1080/0268117X.2004.10555543. S2CID 171203209. /wiki/The_Seventeenth_Century_(journal)
Malcolm, Noel (September 2004). "Thomas Harrison and his 'ark of studies': an episode in the history of the organization of knowledge". The Seventeenth Century. 19 (2): 196–232 (220–221). doi:10.1080/0268117X.2004.10555543. S2CID 171203209. /wiki/The_Seventeenth_Century_(journal)
Müller-Wille, Staffan; Charmantier, Isabelle (March 2012). "Natural history and information overload: The case of Linnaeus". Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences. 43 (1): 4–15. doi:10.1016/j.shpsc.2011.10.021. PMC 3878424. PMID 22326068. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3878424
Blei, Daniela (2017-12-01). "How the Index Card Cataloged the World". The Atlantic. The Atlantic. Archived from the original on 2021-05-08. Retrieved 4 July 2021. https://web.archive.org/web/20210508022255/https://www.theatlantic.com/technology/archive/2017/12/how-the-index-card-catalogued-the-world/547271/
Haarkötter, Hektor. "'Alles Wesentliche findet sich im Zettelkasten'". heise online (in German). Archived from the original on 2020-07-15. Retrieved 2020-05-31. https://www.heise.de/tp/features/Alles-Wesentliche-findet-sich-im-Zettelkasten-3398418.html
Haarkötter, Hektor. "'Alles Wesentliche findet sich im Zettelkasten'". heise online (in German). Archived from the original on 2020-07-15. Retrieved 2020-05-31. https://www.heise.de/tp/features/Alles-Wesentliche-findet-sich-im-Zettelkasten-3398418.html
Paul, Jean (2013) [1796]. Leben des Quintus Fixlein, aus funfzehn Zettelkästen gezogen. Nebst einem Mustheil und einigen Jus de tablette. Geschichte meiner Vorrede zur zweiten Auflage des Quintus Fixlein. Werke: historisch-kritische Ausgabe (in German). Vol. VI, 1. Berlin: de Gruyter. doi:10.1515/9783110303711. ISBN 978-3-484-10917-9. OCLC 881295864. 978-3-484-10917-9
Helbig, Daniela K. (17 April 2019). "Ruminant machines: a twentieth-century episode in the material history of ideas". Journal of the History of Ideas Blog. Retrieved 8 June 2021. https://jhiblog.org/2019/04/17/ruminant-machines-a-twentieth-century-episode-in-the-material-history-of-ideas/
Langlois, Charles Victor; Seignobos, Charles (1912) [1897]. Introduction to the Study of History. Translated by G. G. Berry. New York: Henry Holt and Company. OCLC 2849202. /wiki/Charles-Victor_Langlois
Good, Carter V.; Scates, Douglas E. (1954). "Note-taking and Note Systems". Methods of Research: Educational, Psychological, Sociological. New York: Appleton-Century-Crofts. pp. 187–188. doi:10.1037/13206-004. OCLC 310881. https://archive.org/details/methodsofresearc0000good/page/187
Antonin, Sertillanges (1948). The Intellectual Life: Its Spirit, Conditions, Methods. Translated by Mary Ryan. Westminster, Maryland: The Newman Press. pp. 186–198. OCLC 6033719. Translated from the 1934 new French edition. For other editions, see: "Sertillanges, A.-D 1863–1948". WorldCat. Retrieved 3 November 2021. /wiki/Antonin_Sertillanges
Antonin, Sertillanges (1948). The Intellectual Life: Its Spirit, Conditions, Methods. Translated by Mary Ryan. Westminster, Maryland: The Newman Press. pp. 186–198. OCLC 6033719. Translated from the 1934 new French edition. For other editions, see: "Sertillanges, A.-D 1863–1948". WorldCat. Retrieved 3 November 2021. /wiki/Antonin_Sertillanges
Chavigny, Paul (1918). Organisation du travail intellectuel: recettes pratiques à l'usage des étudiants de toutes les facultés et de tous les travailleurs (in French). Paris: Delagrave. hdl:2027/loc.ark:/13960/t3cz41v8p. OCLC 489977122. https://hdl.handle.net/2027/loc.ark:/13960/t3cz41v8p
Antonin, Sertillanges (1948). The Intellectual Life: Its Spirit, Conditions, Methods. Translated by Mary Ryan. Westminster, Maryland: The Newman Press. pp. 186–198. OCLC 6033719. Translated from the 1934 new French edition. For other editions, see: "Sertillanges, A.-D 1863–1948". WorldCat. Retrieved 3 November 2021. /wiki/Antonin_Sertillanges
Dow, Earle W. (1924). Principles of a Note-system for Historical Studies. Century Historical Series. New York: The Century Company. OCLC 4562633. https://books.google.com/books?id=evg1AAAAMAAJ
Hockett, Homer Carey (1948) [1931]. "Note-taking". Introduction to Research in American History (2nd ed.). New York: Macmillan. pp. 46–55. OCLC 1374221. https://archive.org/details/introductiontore0000home_o8w7/page/46
Webb, Sidney; Webb, Beatrice (1932). "The Art of Note-taking". Methods of Social Study. London; New York: Longmans, Green & Co. pp. 83–97. OCLC 904856. An earlier version of this chapter was published as: Webb, Beatrice (1926). "The Art of Note-taking". My Apprenticeship. London; New York: Longmans, Green & Co. pp. 412–421. ISBN 978-0-404-14045-8. OCLC 392496. 978-0-404-14045-8
Alexander, Carter; Burke, Arvid James (1958) [1935]. "Note-taking in Work with Library Materials". How to Locate Educational Information and Data: An Aid to Quick Utilization of the Literature of Education (4th ed.). New York: Teachers College, Columbia University. pp. 168–180. hdl:2027/uc1.b3389054. OCLC 14603864. This book, which was also translated into Spanish, grew out of a pamphlet titled Educational Research first published in 1927. For other editions, see: "Alexander, Carter 1881–1965". WorldCat. Retrieved 16 September 2022. https://hdl.handle.net/2027/uc1.b3389054?urlappend=%3Bseq=190
Williams, Cecil B. (1963) [1940]. "Notes and Note-taking". A Research Manual for College Studies and Papers (3rd ed.). New York: Harper & Row. pp. 95–105. OCLC 1264058764. Chapter 9, "Notes Into Manuscript", describes how notes from a card file are used during the process of writing a work. The first edition, titled A Research Manual, was co-authored with Allan H. Stevenson. https://archive.org/details/researchmanualfo03will/page/95
Gottschalk, Louis Reichenthal (1969) [1950]. "Note-taking". Understanding History: A Primer of Historical Method (2nd ed.). New York: Knopf. pp. 73–85. OCLC 3861. /wiki/Louis_R._Gottschalk
Sanders, Chauncey (1952). "Tools of Research". An Introduction to Research in English Literary History: With a Chapter on Research in Folklore. New York: Macmillan. pp. 86–88. OCLC 990373. https://archive.org/details/introductiontore0000sand/page/86
Barzun, Jacques; Graff, Henry F. (2004) [1957]. The Modern Researcher (6th ed.). Belmont, CA: Thomson/Wadsworth. pp. 22–31, 176–183. ISBN 978-0-15-505529-2. OCLC 53244810. The authors opine that "the researcher who has to travel is better off with notebooks than with stacks of cards" (23). Chapter 8, "Organizing", describes how notes from a card file are used during the process of writing a work. 978-0-15-505529-2
Shafer, Robert Jones; et al., eds. (1980) [1969]. "Research Notes". A Guide to Historical Method. The Dorsey Series in History (3rd ed.). Homewood, Ill.: Dorsey Press. pp. 117–126. ISBN 978-0-256-02313-8. OCLC 6400352. 978-0-256-02313-8
Blair, Ann M. (2010). Too Much to Know: Managing Scholarly Information before the Modern Age. New Haven: Yale University Press. doi:10.12987/9780300168495. ISBN 978-0-300-11251-1. JSTOR j.ctt1nptsm. OCLC 601347978. S2CID 187487133. 978-0-300-11251-1
Heyde, Johannes Erich (1933). Technik des wissenschaftlichen Arbeitens: eine Anleitung, besonders für Studierende (in German) (4th ed.). Berlin: Junker und Dünnhaupt. OCLC 38252126. For other editions, see: "Heyde, Johannes Erich 1892–1979". WorldCat. Retrieved 22 August 2022. /wiki/OCLC_(identifier)
Pomeroy, Earl (March 1953). "Frederic L. Paxson and His Approach to History". The Mississippi Valley Historical Review. 39 (4): 673–692. doi:10.2307/1895394. JSTOR 1895394. /wiki/Earl_S._Pomeroy
Pomeroy, Earl (March 1953). "Frederic L. Paxson and His Approach to History". The Mississippi Valley Historical Review. 39 (4): 673–692. doi:10.2307/1895394. JSTOR 1895394. /wiki/Earl_S._Pomeroy
Hollier, Denis (2005). "Notes (On the Index Card)". October. 112 (Spring): 35–44. doi:10.1162/0162287054223918. JSTOR 3397642. S2CID 57564798. /wiki/Doi_(identifier)
Benjamin, Walter; Tiedemann, Rolf (1999). The Arcades Project. Translated by Howard Eiland and Kevin McLaughlin. Cambridge, Mass.: Belknap Press. ISBN 978-0-674-04326-8. OCLC 41176710.Hanssen, Beatrice, ed. (2006). Walter Benjamin and the Arcades Project. Walter Benjamin Studies Series. London; New York: Continuum. ISBN 978-0-8264-6386-9. OCLC 53912748. 978-0-674-04326-8978-0-8264-6386-9
Hollier, Denis (2005). "Notes (On the Index Card)". October. 112 (Spring): 35–44. doi:10.1162/0162287054223918. JSTOR 3397642. S2CID 57564798. /wiki/Doi_(identifier)
Krapp, Peter (2006). "Hypertext Avant La Lettre". In Chun, Wendy Hui Kyong; Keenan, Thomas (eds.). New Media, Old Theory: A History and Theory Reader. New York: Routledge. pp. 359–373 (363). doi:10.4324/9780203643839-36. ISBN 978-0-415-94223-2. OCLC 60492092. 978-0-415-94223-2
Wilken, Rowan (2010). "The card index as creativity machine" (PDF). Culture Machine. 11: 7–30. Retrieved 23 April 2022. https://culturemachine.net/wp-content/uploads/2019/01/373-604-1-PB.pdf
Calvet, Louis-Jean (1994). Roland Barthes: A Biography. Bloomington, IN: Indiana University Press. ISBN 978-0-253-34987-3. OCLC 31295073. 978-0-253-34987-3
Wilken, Rowan (2010). "The card index as creativity machine" (PDF). Culture Machine. 11: 7–30. Retrieved 23 April 2022. https://culturemachine.net/wp-content/uploads/2019/01/373-604-1-PB.pdf
Barthes, Roland (1994) [1975]. Roland Barthes. Translated by Richard Howard. Berkeley: University of California Press. p. 75. ISBN 978-0-520-08783-5. OCLC 29954608. 978-0-520-08783-5
Barthes, Roland (2010). Mourning Diary: October 26, 1977-September 15, 1979. Translated by Richard Howard. New York: Hill and Wang. ISBN 978-0-8090-6233-1. OCLC 526809468. 978-0-8090-6233-1
Hollier, Denis (2005). "Notes (On the Index Card)". October. 112 (Spring): 35–44. doi:10.1162/0162287054223918. JSTOR 3397642. S2CID 57564798. /wiki/Doi_(identifier)
Yacavone, Kathrin (2020). "Picturing Barthes: The Photographic Construction of Authorship". In Knight, Diana (ed.). Interdisciplinary Barthes. Proceedings of the British Academy. Vol. 228. Published for the British Academy by Oxford University Press. pp. 97–117 (105). doi:10.5871/bacad/9780197266670.003.0007. ISBN 978-0-19-726667-0. OCLC 1130361272. S2CID 242966795. See also: Cartier-Bresson photograph on ResearchGate. 978-0-19-726667-0
Helbig, Daniela K. (17 April 2019). "Ruminant machines: a twentieth-century episode in the material history of ideas". Journal of the History of Ideas Blog. Retrieved 8 June 2021. https://jhiblog.org/2019/04/17/ruminant-machines-a-twentieth-century-episode-in-the-material-history-of-ideas/
Helbig, Daniela K. (January 2019). "Life without Toothache: Hans Blumenberg's Zettelkasten and History of Science as Theoretical Attitude". Journal of the History of Ideas. 80 (1): 91–112. doi:10.1353/jhi.2019.0005. hdl:21.11116/0000-0002-F4A8-D. PMID 30713207. S2CID 73416765. https://pure.mpg.de/rest/items/item_3026314/component/file_3327044/content
Helbig, Daniela K. (17 April 2019). "Ruminant machines: a twentieth-century episode in the material history of ideas". Journal of the History of Ideas Blog. Retrieved 8 June 2021. https://jhiblog.org/2019/04/17/ruminant-machines-a-twentieth-century-episode-in-the-material-history-of-ideas/
Beam, Alex (2008). A Great Idea at the Time: The Rise, Fall, and Curious Afterlife of the Great Books. New York: PublicAffairs. ISBN 978-1-58648-487-3. OCLC 191926328.Campbell, James (2008-11-14). "Heavy Reading". The New York Times. Retrieved 29 October 2021. 978-1-58648-487-3
Matthews, Michael R., ed. (2019). Mario Bunge: a Centenary Festschrift. Cham: Springer-Verlag. p. 1. doi:10.1007/978-3-030-16673-1. ISBN 9783030166724. OCLC 1109956992. 9783030166724
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