Robakowski, Piotr, Jerzy Modrzynski, y Mohammed Idris. 1997. «Adaptation of Seedling Growth to the Altitude: A Case of the Norway Spruce from the Polish Sudety Mountains». Pirineos 149-150 (diciembre):81-89. https://doi.org/10.3989/pirineos.1997.v149-150.127.