Breuning-Madsen, Henrik. 1989. “Paul A. Delcourt, Hazel R. Delcourt: Longterm Forest Dynamics of the Temperate Zone: A Case Study of Late-Quaternary Forests in Eastern North America. (Ecological Studies, Vol. 63.)”. Geografisk Tidsskrift 89 (januar). https://tidsskrift.dk/geografisktidsskrift/article/view/44712.