Challenges of a changing world :
festschrift to Willy Østreng on his 50th birthday May 4th 1991.
APA Citation
Østreng, W., Fridtjof Nansen-stiftelsen på Polhøgda. (1991). Challenges of a changing world: festschrift to Willy Østreng on his 50th birthday May 4th 1991. [S.l.]: Fridtjof Nansen Institute.
MLA Citation
Østreng, Willy, 1941-, and Fridtjof Nansen-stiftelsen på Polhøgda. Challenges of a Changing World: Festschrift to Willy Østreng On His 50th Birthday May 4th 1991. [S.l.]: Fridtjof Nansen Institute, 1991.
Warning: These citations may not always be complete (especially for serials).