WIELEN P VAN DER (1961) Oölogische nidologische and communications, 1959-II and 1960. Early broods of Pied Flycatcher Ficedula hypoleuca. LIMOSA 34 (3): 270-270.
Oölogische nidologische and communications, 1959-II and 1960. Early broods of Pied Flycatcher Ficedula hypoleuca
