Bird numbers 1992 : International Conference of IBCC and EOAC; Program & Abstracts, 14-18 September 1992, Noordwijkerhout, The Netherlands
Bird numbers 1992 : International Conference of IBCC and EOAC; Program & Abstracts, 14-18 September 1992, Noordwijkerhout, The Netherlands / [Honorary president: K.H. Voous ; exec. comm.: Gerard Boere ... et al.]