R. P. Zentner, P. Basnyat, S. A. Brandt, A. G. Thomas, D. Ulrich, C. A. Campbell, C. N. Nagy, B. Frick, R. Lemke, S. S. Malhi and M. R. Fernandez, “Input management and crop diversity: Effects on economic returns and riskiness of cropping systems in the semiarid Canadian Prairie,” Renewable Agricultural Food Systems, 2011, pp. 1-16. doi:10.1017/S1742170510000591
 M. H. Entz, R. Guilford and R. Gulden, “Crop yield and soil nutrient status on 14 organic farms in the eastern part of the northern Great Plains,” Canadian Journal of Plant Science, Vol. 81, 2001, pp. 351-354. doi:10.4141/P00-089
 C. A. Watson, P. Atkinson, P. Gosling, L. R. Jackson and F. W. Ryans, “Managing soil fertility in organic farming systems,” Soil Use and Management, Vol. 18, 2002, pp. 239-247. doi:10.1079/SUM2002131
 S. S. Malhi, S. A. Brandt, R. Lemke, A. P. Moulin and R. P. Zentner, “Effects of input level and crop diversity on soil nitrate-N, extractable P, aggregation, organic C and N, and N and P balance in the Canadian Prairie,” Online. Nutrient Cycling in Agroecosystems, Vol. 84, 2009, pp. 1-22. doi:10.1007/s10705-008-9220-0
 P. R. Miller, D. E. Buschena, C. A. Jones and J. A. Holmes, “Transition from intensive tillage to no-tillage and organic diversified cropping systems,” Agronomy Journal, Vol. 100, 2009, pp. 591-599. doi:10.2134/agronj2007.0190
 R. P. Zentner, C. A. Campbell, V. O. Biederbeck, F. Selles, R. Lemke, P. G. Jefferson, and Y. Gan, “Long-term assessment of management of an annual legume green manure crop for fallow replacement in the Brown soil zone,” Canadian Journal of Plant Science, Vol. 84, 2004, pp. 11-22. doi:10.4141/P02-188
 N. Z. Lupwayi and Y. K. Soon, “Nitrogen release from field pea residue and soil inorganic N in a pea-wheat crop rotation in northwestern Canada,” Canadian Journal of Plant Science, Vol. 89, 2009, pp. 239-246. doi:10.4141/CJPS08019
 R. Paolini, F. Caporali and E. Campiglia, “Yield response, complementarity and competitive ability of bread wheat (Triticum aestivum L.) and pea (Pisum sativum L.) in mixtures,” Agricoltura Mediterranea, Vol. 123, 1993, pp. 114-121.
 H. Hauggaard-Nielsen and E. S. Jensen, ?Evaluating pea and barley cultivars for complementarity in intercropping at different levels of soil N availability,” Field Crops Research, Vol. 72, 2001, pp. 185-196. doi:10.1016/S0378-4290(01)00176-9
 A. R. Szumigalski and R. C. Van Acker, “Land equivalent ratios, light interception, and water use in intercrops in the presence or absence of in-crop herbicides,” Agronomy Journal, Vol. 100, 2008, pp. 1145-1154. doi:10.2134/agronj2006.0343
 S. S. Malhi, “Short-term residual effects of various amendments on organic C and N, and available nutrients in soil under organic crop production,” Agricultural Sciences, Vol. 3, 2012, pp. 375-384.
 R. J. Noel and L. G. Hambleton, “Collaborative study of a semi-automated method for the determination of crude protein in animal feeds,” Journal of Association of Official Analytical Chemists, Vol. 59, 1976, pp. 134-140.
 W. F. Milbury, V. T. Stack and F. L. Doll, “Simultaneous determination of total phosphorus and total Kjeldahl nitrogen in activated sludge with the Technicon continuous digestor system,” In Technicon International Congress, Advances in Automatic Analysis, Industrial Analysis, Vol. II, 1970, pp. 299-304.
 J. B. Jones, “Plant tissue analysis in micronutrients,” SSSA, Chapter 13, Micronutrients in Agriculture, 2nd Edition, SSSA Book series #4. ICP, Private communication with technical personnel, Questron Technologies Corp., Mississauga, Ontario, Canada. 1991.
 R. M. N. Kucey, “Increased phosphorus uptake by wheat and field beans inoculated with a phosphorus-solubilizing Penicillium bilaji strain and with vesicular-arbuscular mycorrhizal fungi,” Applied Environmental Microbiology, Vol. 53, 1987, pp. 2699-2703.
 P. M. Chalk, R. F. Souze, B. J. R. Urquiaga and R. M. Boddey, “The role of arbuscular mychorrhiza in legume sybiotic performance,” Soil Biology and Biochemistry, Vol. 38, 2006, pp. 2944-2951. doi:10.1016/j.soilbio.2006.05.005
 A. S. Jeng, T. K. Haraldsen, R. Gronlund and P. A. Pedersen, “Meat and bone meal as nitrogen and phosphorus fertilizer to cereals and ryegrass,” Nutrient Cycling in Agroecosystems, Vol. 76, 2009, pp. 183-191. doi:10.1007/s10705-005-5170-y
 S. A. Brandt, R. P. Zentner, O. O. Olfert, A. G. Thomas and S. S. Malhi, “Input level and crop diversity strategies to enhance sustainability of crop production and soil quality in the Northern Great Plains of North America,” In: S. S. Malhi, Y. Gan, J. J. Schoenau, R. L. Lemke and M. A. Liebig, Recent Trends in Soil Science and Agronomy Research in the Northern Great Plains of North America, Research Signpost (2010), Trivandrum, Kerala, India, Chapter 8, pp. 179-199. 2010.
 M. H. Entz, W. J. Bullied, D. A. Foster, R. Gulden and K. Vessey, “Extraction of subsoil nitrogen by alfalfa, alfalfa-wheat and perennial grass systems,” Agronomy Journal, Vol. 93, 2001, pp. 495-503. doi:10.2134/agronj2001.933495x
 M. Takeda, “Solubilization of rock phosphate by Penicillium bilaiae: Mechanisms and the feasibility for use in organic crop production,” M.Sc. thesis, University of Saskatchewan, Saskatoon, Saskatchewan, Canada. 2004.
 S. C. Gleddie, D. Schlechte and G. Turnbull, “Effect of inoculation with Penicillium bilaii (Provide?) on phosphate uptake and yield of canola in western Canada,” Pages 155-160 in Proceedings of Alberta Soil Science Workshop, Edmonton, Alberta, Canada. 1993.
 M. Badaruddin and D. W. Meyer, “Grain legume effects on soil nitrogen, grain yield, and nitrogen nutrition of wheat,” Crop Science, Vol. 34, 1994, pp. 1304-1309. doi:10.2135/cropsci1994.0011183X003400050030x
 H. J. Beckie and S. A. Brandt, “Nitrogen contribution of field pea in annual cropping systems. 1. Nitrogen residual effect,” Canadian Journal of Plant Science, Vol. 77, 1997, pp. 311-322. doi:10.4141/P96-161
 L. E. Welty, L. S. Prestbye, R. E. Engel, R. A. Larson, R. H. Lokerman, R. S. Speilman, J. R. Sims, L. I. Hart, G. D. Kushnak and A. L. Dubbs, “Nitrogen contribution of annual legumes to subsequent barley production,” Applied Agricultural Research, Vol. 3, 1988, pp. 98-104.
 D. W. A. Przednowek, M. H. Entz, B. Irvine, D. N. Flate and J. R. Thiessen Martens, “Rotational yield and apparent N benefits of grain legumes in southern Manitoba,” Canadian Journal of Plant Science, Vol. 84, 2004, pp. 1093-1096. doi:10.4141/P04-032