Não informado. (1949). Engineering report. Iowa Engineering Experiment Station.
Chicago-referens (17:e uppl.)Não informado. Engineering Report. Ames, Iowa: Iowa Engineering Experiment Station, 1949.
MLA-referens (8:e uppl.)Não informado. Engineering Report. Iowa Engineering Experiment Station, 1949.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.