APA-viite (7. p.)

Heap, G. (1992). Structures approach to systems development. McGraw-Hill.

Chicago-viite (17. p.)

Heap, Gary. Structures Approach to Systems Development. London: McGraw-Hill, 1992.

MLA-viite (9. p.)

Heap, Gary. Structures Approach to Systems Development. McGraw-Hill, 1992.