Dariusz Krzyszkowski, Zofia Balwierz, and Wladyslaw Pyszyriski. “Aspects of Weichselian Middle Pleniglacial Stratigraphy and Vegetation in Central Poland”. Netherlands Journal of Geosciences, vol. 72, Jan. 1993, pp. 131-42, https://njgjournal.nl/index.php/njg/article/view/12504.