Lykouressis, D.P. and Emden Η.V. 1983. Factors affecting the potential increase rate (e’, PIR), as defined by Hughes, in populations of Sitobion αvenαe (F.) (Hemiptera: Aphididae. ENTOMOLOGIA HELLENICA. 1, (Jan. 1983), 53–57. DOI:https://doi.org/10.12681/eh.13894.