Hewitt, T. H. (1974). Advanced geometrical and engineering drawing. English Universities Press.
Lua i Stíl Chicago (17ú heag.)Hewitt, Thomas H. Advanced Geometrical and Engineering Drawing. London: English Universities Press, 1974.
Lua MLA (9ú heag.)Hewitt, Thomas H. Advanced Geometrical and Engineering Drawing. English Universities Press, 1974.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.