Bijkerk,C. (1975). Recreation values of forests and parks. Institute for land and water management research.
Trích dẫn kiểu ChicagoBijkerk,C. Recreation Values of Forests and Parks. Netherlands: Institute for land and water management research, 1975.
Trích dẫn MLABijkerk,C. Recreation Values of Forests and Parks. Institute for land and water management research, 1975.
Cảnh báo: Các trích dẫn này có thể không phải lúc nào cũng chính xác 100%.