Não informado. (1930). Program of activities of the Chicago Academy of Sciences. Chicago Academy of Sciences.
Citação do estilo Chicago (17ª ed.)Não informado. Program of Activities of the Chicago Academy of Sciences. Chicago, Ill: Chicago Academy of Sciences, 1930.
Citação MLA (8ª ed.)Não informado. Program of Activities of the Chicago Academy of Sciences. Chicago Academy of Sciences, 1930.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.