Howlett, B. G., R. C. Butler, M. K. Walker, and D. A. Teulon. “Are Insect Flower Visitor Assemblages Distinguishable Between Brassica Napus and B. Rapa?”. New Zealand Plant Protection, Vol. 71, July 2018, pp. 189-97, doi:10.30843/nzpp.2018.71.162.