Rudenko G, Le Blancq S, Smith J, Lee MG, Rattray A, Van der Ploeg LH (July 1990). "Procyclic acidic repetitive protein (PARP) genes located in an unusually small alpha-amanitin-resistant transcription unit: PARP promoter activity assayed by transient DNA transfection of Trypanosoma brucei". Mol. Cell. Biol. 10 (7): 3492–504. doi:10.1128/MCB.10.7.3492. PMC 360784. PMID 1694012. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC360784
Acosta-Serrano A, Vassella E, Liniger M, Kunz Renggli C, Brun R, Roditi I, Englund PT (February 2001). "The surface coat of procyclic Trypanosoma brucei: programmed expression and proteolytic cleavage of procyclin in the tsetse fly". Proc. Natl. Acad. Sci. U.S.A. 98 (4): 1513–8. Bibcode:2001PNAS...98.1513A. doi:10.1073/pnas.98.4.1513. PMC 29288. PMID 11171982. /wiki/Paul_Englund
Bütikofer P, Ruepp S, Boschung M, Roditi I (September 1997). "'GPEET' procyclin is the major surface protein of procyclic culture forms of Trypanosoma brucei brucei strain 427". Biochem. J. 326 (2): 415–23. doi:10.1042/bj3260415. PMC 1218686. PMID 9291113. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1218686