Não informado. (1887). Bulletin of the Pennsylvania Agricultural Experiment Station. Pennsylvania Agricultural Experiment Station.
Citação do estilo Chicago (17ª ed.)Não informado. Bulletin of the Pennsylvania Agricultural Experiment Station. Harrisburg, Pa: Pennsylvania Agricultural Experiment Station, 1887.
Citação MLA (8ª ed.)Não informado. Bulletin of the Pennsylvania Agricultural Experiment Station. Pennsylvania Agricultural Experiment Station, 1887.
Atenció: Aquestes cites poden no estar 100% correctes.