Ratyńska, H., M. Grodzki, B. Waldon, and E. Wachowiak. “Introduction of Alien Tree Species and Its Influence on Floristical Composition and Vegetation Structure of Acidophilous Oak Forests: The Experimental Plots in the Zielonka Forest”. Acta Universitatis Lodziensis. Folia Biologica Et Oecologica, vol. 7, Dec. 2011, pp. 177-90, doi:10.2478/v10107-009-0024-z.