Some of the principal insect enemies of coniferous forests in the United States

Chicago citation style
Hopkins, A. D. (Andrew Delmar), 1857-1948. Some of the principal insect enemies of coniferous forests in the United States. 1903. Retrieved from the Digital Public Library of America, http://catalog.hathitrust.org/Record/009602772. (Accessed October 20, 2018.)
APA citation style
Hopkins, A. D. (Andrew Delmar), 1857-1948, (1903) Some of the principal insect enemies of coniferous forests in the United States. Retrieved from the Digital Public Library of America, http://catalog.hathitrust.org/Record/009602772
MLA citation style
Hopkins, A. D. (Andrew Delmar), 1857-1948. Retrieved from the Digital Public Library of America <http://catalog.hathitrust.org/Record/009602772>.
Note: These citations are programmatically generated and may be incomplete.