John Rickard

Glymmatacanthus St.John & Worthen, 1875 Ctenacanthidae. GBIF. [2024-02-08]. （原始内容存档于2024-02-08）.  Hodnett, John-Paul M.; Toomey, Rickard; Olson, Rickard; Tolleson

Società Paleontologica Italiana 39 (2000): 225-228. John-Paul M. Hodnett, Rickard Toomey, Rickard Olson, Justin S. Tweet and Vincent L. Santucci. 2023

Nepenthes rajah. Carnivorous Plant Newsletter 17(2): 55. Michell, John and Rickard, Bob. The Rough Guide to Unexplained Phenomena. Rough Guides. 2000

Napoleonic Historical Society. 2008 [2021-05-25]. （原始内容存档于2008-02-07）.  Rickard, John. Siege of Astorga, 21 March-22 April 1810. 2021 [2021-05-25]. （原始内容存档于2021-05-23）

251–260. doi:10.1080/02724634.1998.10011054.  Hodnett, John-Paul M.; Toomey, Rickard; Olson, Rickard; Tolleson, Kelli; Boldon, Richard; Wood, Jack; Tweet