APA način citiranja (7. izdanje)
Heilman, R. B., Voegelin, E., & Embry, C. R. (2004). Robert B. Heilman and Eric Voegelin: A friendship in letters, 1944-1984. University of Missouri Press.
Čikaški stil citiranja (17. izdanje)
Heilman, Robert Bechtold, Eric Voegelin, i Charles R. Embry. Robert B. Heilman and Eric Voegelin: A Friendship in Letters, 1944-1984. Columbia: University of Missouri Press, 2004.
MLA način citiranja (9. izdanje)
Heilman, Robert Bechtold, et al. Robert B. Heilman and Eric Voegelin: A Friendship in Letters, 1944-1984. University of Missouri Press, 2004.
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