APA (7.\xaa ed.)

Hoffman, L., Ebdon, J. S., Dest, W. M., & Dacosta, M. (2010). Effects of nitrogen and potassium on wear mechanisms in perennial ryegrass : 2. anatomical, morphological, and physiological characteristics / L. Hoffman ; J. S. Ebdon ; W. M. Dest ... [et al.]. Crop Science, 50(1).