Pennsylvania State Beekeepers' Association & Pennsylvania State Beekeepers' Association. (1928). Report of the Pennsylvania State Beekeepers' Association. Published by direction of the Secretary of Agriculture Harrisburg Publishing Co., state printer.
Παραπομπή σε μορφή Chicago (17η εκδ.)Pennsylvania State Beekeepers' Association και Pennsylvania State Beekeepers' Association. Report of the Pennsylvania State Beekeepers' Association. Harrisburg, PA: Published by direction of the Secretary of Agriculture Harrisburg Publishing Co., state printer, 1928.
Παραπομπή σε μορφή MLA (8th εκδ.)Pennsylvania State Beekeepers' Association και Pennsylvania State Beekeepers' Association. Report of the Pennsylvania State Beekeepers' Association. Published by direction of the Secretary of Agriculture Harrisburg Publishing Co., state printer, 1928.