MacKellar, Thomas (1893). The American Printer. Philadelphia: MacKellar, Smiths & Jordan Co. pp. 252–254, 311–312. https://archive.org/details/americanprinterm00mack
"Roller". American Dictionary of Printing and Bookmaking. New York: H. Lockwood & Co. 1894. https://archive.org/details/americandiction00paskgoog
Adams, Thomas F. (1861). Typographia; or, the Printer's Instructor. Philadelphia: L. Johnson & Co. pp. 260–266. https://archive.org/details/graphiaorpritypo00adamrich
Blades, William (1891). The Pentateuch of Printing, with a Chapter on Judges. Chicago: A.C. Mclurg and Company. p. 90. https://archive.org/details/pentateuchofprin00bladuoft
Adams, Thomas F. (1861). Typographia; or, the Printer's Instructor. Philadelphia: L. Johnson & Co. pp. 259–260. https://archive.org/details/graphiaorpritypo00adamrich
"Roller". American Dictionary of Printing and Bookmaking. New York: H. Lockwood & Co. 1894. https://archive.org/details/americandiction00paskgoog
"Roller". American Dictionary of Printing and Bookmaking. New York: H. Lockwood & Co. 1894. https://archive.org/details/americandiction00paskgoog
Adams, Thomas F. (1861). Typographia; or, the Printer's Instructor. Philadelphia: L. Johnson & Co. pp. 260–266. https://archive.org/details/graphiaorpritypo00adamrich
Blades, William (1891). The Pentateuch of Printing, with a Chapter on Judges. Chicago: A.C. Mclurg and Company. p. 90. https://archive.org/details/pentateuchofprin00bladuoft
"Roller". American Dictionary of Printing and Bookmaking. New York: H. Lockwood & Co. 1894. https://archive.org/details/americandiction00paskgoog
Harpel, Oscar H. (1870). Harpel's Typograph. Cincinnati: by author. pp. 41–43. https://archive.org/details/harpelstypograph00harp
"Roller". American Dictionary of Printing and Bookmaking. New York: H. Lockwood & Co. 1894. https://archive.org/details/americandiction00paskgoog
MacKellar, Thomas (1893). The American Printer. Philadelphia: MacKellar, Smiths & Jordan Co. pp. 252–254, 311–312. https://archive.org/details/americanprinterm00mack
"Roller". The Printer's Dictionary of Technical Terms. Boston: North End Union School of Printing. 1912. pp. 244–249. https://archive.org/details/printersdictiona00stew
"Roller". American Dictionary of Printing and Bookmaking. New York: H. Lockwood & Co. 1894. https://archive.org/details/americandiction00paskgoog
Harpel, Oscar H. (1870). Harpel's Typograph. Cincinnati: by author. pp. 41–43. https://archive.org/details/harpelstypograph00harp
MacKellar, Thomas (1893). The American Printer. Philadelphia: MacKellar, Smiths & Jordan Co. pp. 252–254, 311–312. https://archive.org/details/americanprinterm00mack
Adams, Thomas F. (1861). Typographia; or, the Printer's Instructor. Philadelphia: L. Johnson & Co. pp. 260–266. https://archive.org/details/graphiaorpritypo00adamrich
Harpel, Oscar H. (1870). Harpel's Typograph. Cincinnati: by author. pp. 41–43. https://archive.org/details/harpelstypograph00harp
"Roller". American Dictionary of Printing and Bookmaking. New York: H. Lockwood & Co. 1894. https://archive.org/details/americandiction00paskgoog
"Roller". The Printer's Dictionary of Technical Terms. Boston: North End Union School of Printing. 1912. pp. 244–249. https://archive.org/details/printersdictiona00stew
MacKellar, Thomas (1893). The American Printer. Philadelphia: MacKellar, Smiths & Jordan Co. pp. 252–254, 311–312. https://archive.org/details/americanprinterm00mack
MacKellar, Thomas (1893). The American Printer. Philadelphia: MacKellar, Smiths & Jordan Co. pp. 252–254, 311–312. https://archive.org/details/americanprinterm00mack
Harpel, Oscar H. (1870). Harpel's Typograph. Cincinnati: by author. pp. 44–45. https://archive.org/details/harpelstypograph00harp
"Roller". The Printer's Dictionary of Technical Terms. Boston: North End Union School of Printing. 1912. pp. 244–249. https://archive.org/details/printersdictiona00stew
"Roller". American Dictionary of Printing and Bookmaking. New York: H. Lockwood & Co. 1894. https://archive.org/details/americandiction00paskgoog