Preston F.W. (1948). "The commonness, and rarity, of species". Ecology. 29 (3): 254–283. doi:10.2307/1930989. JSTOR1930989.
Papp L., Izsák J. (1997). "Bimodality in occurrence classes: a direct consequence of lognormal and logarithmic series distribution of abundances – a numerical experimentation". Oikos. 79 (1): 191–194. doi:10.2307/3546107. JSTOR3546107.
Preston F.W. (1948). "The commonness, and rarity, of species". Ecology. 29 (3): 254–283. doi:10.2307/1930989. JSTOR1930989.
Papp L., Izsák J. (1997). "Bimodality in occurrence classes: a direct consequence of lognormal and logarithmic series distribution of abundances – a numerical experimentation". Oikos. 79 (1): 191–194. doi:10.2307/3546107. JSTOR3546107.