https://www.jstor.org/stable/43552152?seq=1 https://www.jstor.org/stable/43552152?seq=1 and https://www.researchgate.net/publication/227283604_Population_Hete

https://www.jstor.org/stable/43552152?seq=1 https://www.jstor.org/stable/43552152?seq=1 and https://www.researchgate.net/publication/227283604_Population_Heterogeneity_and_State_Dependence_State_of_the_Evidence_and_Directions_For_Future_Research https://www.researchgate.net/publication/227283604_Populatio...