Bulgarian Academy of ScienceCentral library of BASNALIS Union Catalogue – a national catalogue of the academic libraries in BulgariaOn-line resources of the library of BASSONIXNational Science FundMinistry of Education and ScienceProf. Marin Drinov Academic Publishing House boletales.comEast and South European Network for Invasive Alien Species (ESENIAS)International Seminar of Ecology (link) EU Research and Innovation programme Horizon 2020 (link to Bulgarian portal) Science portal of MES (link)