APA

Hedlin A. F., Yates H. O., Tovar D. C., Ebel B. H., Koerber T. W. & Merkel E. P. (1981). Cone and Seed Insects of North American Conifers. Ottawa: Canadian Forestry Service.

Chicago

Hedlin Alan F, Yates Harry O, Tovar David Cibrian, Ebel Bernard H, Koerber Thomas W and Merkel Edward P. 1981. Cone and Seed Insects of North American Conifers. Ottawa: Canadian Forestry Service.

Harvard

Hedlin A. F., Yates H. O., Tovar D. C., Ebel B. H., Koerber T. W. and Merkel E. P. (1981). Cone and Seed Insects of North American Conifers. Ottawa: Canadian Forestry Service.

MLA

Hedlin Alan F, Yates Harry O, Tovar David Cibrian, Ebel Bernard H, Koerber Thomas W and Merkel Edward P. Cone and Seed Insects of North American Conifers. Ottawa: Canadian Forestry Service. 1981.