Não informado. (1892). Contributions from the Botanical Laboratory of the University of Pennsylvania. University of Pennsylvania.
Citação do estilo Chicago (17ª ed.)Não informado. Contributions from the Botanical Laboratory of the University of Pennsylvania. Philadelphia, Pa: University of Pennsylvania, 1892.
Citação MLA (8ª ed.)Não informado. Contributions from the Botanical Laboratory of the University of Pennsylvania. University of Pennsylvania, 1892.
警告:这些引文格式不一定是100%准确.