APA استشهاد

Hela, I., & Laevastu, T. (1961). Fisheries hydrograph. Fishing news.

استشهاد بنمط شيكاغو

Hela, Ilmo, و Taivo Laevastu. Fisheries Hydrograph. London: Fishing news, 1961.

MLA استشهاد

Hela, Ilmo, و Taivo Laevastu. Fisheries Hydrograph. Fishing news, 1961.