1. ACPC, 2005. Alberta Canola Producers Commission; http://www.canola.ab.ca/index.cgi?futmon=May05&unit=b.
2. AFRD, 2003. Agriculture, Food and Rural Development, Alberta Government, Crop Enterprise cost and return calculator; http://www.agric.gov.ab.ca/app24/costcalculators/crop/getcrops.jsp.
3. AG, 2005. Alberta Government; Farmer reported variety yields for Peace River soil zone-canola; http://www1.agric.gov.ab.ca/$department/deptdocs.nsf/all/agdex2854.
4. The importance of bees Apoidea as pollinators of crop plants;Banaszak;Wiad. Ekol.,1978
5. Use of genetic markers to quantify bumblebee foraging range and nest density;Darvill;Oikos,2004