¹ Faculty of Silviculture and Forest Engineering, Transylvania University of Brasov, Brasov, RO

² Forest Research, Northern Research Station, Roslin, Midlothian, UK

³ INRAe Centre Val de Loire, Ardon, Orléans, FR

⁴ Faculty of Forest Sciences and Forest Ecology, University Georg-August, Göttingen, DE

⁵ University of Forestry, Sofia, BG

⁶ Department of Silviculture, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, CZ

⁷ Croatian Forest Research Institute, Jastrebarsko, HR

⁸ Foundation Edmund Mach, San Michele all’Adige, IT

⁹ Biotechnical Faculty, University of Ljubljana, Ljubljana, SI

¹⁰ Institute of Lowland Forestry and Environment, Novi Sad, RS

¹¹ National Forest Centre, Forest Research Institute, Zvolen, SK

¹² Faculty of Ecology and Environmental Sciences, Technical University in Zvolen, Zvolen, SK

¹³ Faculty of Agricultural and Food Sciences and Environmental Management, University of Debrecen, Debrecen, HU

¹⁴ Faculty of Forestry, University of Banja Luka, Banja Luka, BA

¹⁵ Department of Silviculture, Faculty of Forestry, Kastamonu University, Kastamonu, TR

¹⁶ Department of Silviculture, Ukrainian National Forestry University, Lviv, UA

¹⁷ Faculty of Horticulture and Forestry, Banat’s University of Agricultural Sciences and Veterinary Medicine, Timisoara, RO

¹⁸ Vâlcea County Branch, National Forest Administration-ROMSILVA, Râmnicu-Vâlcea, RO