APA (6th ed.):
ProCon.org. (2011, December 30). Medical Marijuana Historical Timeline. Retrieved from https://www.procon.org/medical-marijuana-historical-timeline/
[Editor's Note: The APA citation style requires double spacing within entries.]
Chicago (17th ed.):
ProCon.org, "Medical Marijuana Historical Timeline," ProCon.org. last modified December 30, 2011. https://www.procon.org/medical-marijuana-historical-timeline/.
MLA (8th ed.):
ProCon.org, "Medical Marijuana Historical Timeline." ProCon.org. 30 Dec. 2011, www.procon.org/medical-marijuana-historical-timeline/
[Editor’s Note: The MLA citation style requires double spacing within entries.]
Turabian (8th ed.):
ProCon.org. "Medical Marijuana Historical Timeline." ProCon.org. Last modified on December 30, 2011. Accessed April 14, 2021. https://www.procon.org/medical-marijuana-historical-timeline/