Klinkhamer, Peter G. L. (March 1995). "Plant allometry: The scaling of form and process : by Karl J. Niklas University of Chicago Press, 1994". Trends in Ecology & Evolution. 10 (3): 134. doi:10.1016/S0169-5347(00)89015-1.
gf.org
"Karl J. Niklas". John Simon Guggenheim Memorial Foundation. Archived from the original on 22 June 2011. Retrieved 11 February 2010.