APA-viite (7. p.)

Helm, F. C. (1968). The economics of co-operative enterprise. Co-operative College, Tanzania ; In association with University of London Press.

Chicago-viite (17. p.)

Helm, Franz C. The Economics of Co-operative Enterprise. [Moshi, Tanzania] : London: Co-operative College, Tanzania ; In association with University of London Press, 1968.

MLA-viite (8. p.)

Helm, Franz C. The Economics of Co-operative Enterprise. Co-operative College, Tanzania ; In association with University of London Press, 1968.