APA
International Geological Congress, Armstrong J. E., . (19). International Geological Congress, twenty-fourth session, Canada 1972. Ottawa: .
Chicago
International Geological Congress, Armstrong John E, . 19. International Geological Congress, twenty-fourth session, Canada 1972. Ottawa: .
Harvard
International Geological Congress, Armstrong J. E., . (19). International Geological Congress, twenty-fourth session, Canada 1972. Ottawa: .
MLA
International Geological Congress, Armstrong John E, . International Geological Congress, twenty-fourth session, Canada 1972. Ottawa: . 19.