Παραπομπή σε μορφή APA (7η εκδ.)

Harrop, P. (1966). Exercises in engineering drawing. Book 1: A set of graded examples for technical schools, institutes and colleges. Macmillan.

Παραπομπή σε μορφή Chicago (17η εκδ.)

Harrop, P.F. Exercises in Engineering Drawing. Book 1: A Set of Graded Examples for Technical Schools, Institutes and Colleges. London: Macmillan, 1966.

Παραπομπή σε μορφή MLA (8th εκδ.)

Harrop, P.F. Exercises in Engineering Drawing. Book 1: A Set of Graded Examples for Technical Schools, Institutes and Colleges. Macmillan, 1966.