Berry, W. D. (1984). Nonrecursive causal models. Sage Publications.
Lua i Stíl Chicago (17ú heag.)Berry, William Dale. Nonrecursive Causal Models. Beverly Hills, Calif.: Sage Publications, 1984.
Lua MLA (8ú heag.)Berry, William Dale. Nonrecursive Causal Models. Sage Publications, 1984.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.