APA
Wroclaw University, . (1990). proceedings of the Symposium on Biology and Ecology of European Orchids. Wroclaw: Wydawnictwo Uniwersytetu Wroclawskiego.
Chicago
Wroclaw University, . 1990. proceedings of the Symposium on Biology and Ecology of European Orchids. Wroclaw: Wydawnictwo Uniwersytetu Wroclawskiego.
Harvard
Wroclaw University, . (1990). proceedings of the Symposium on Biology and Ecology of European Orchids. Wroclaw: Wydawnictwo Uniwersytetu Wroclawskiego.
MLA
Wroclaw University, . proceedings of the Symposium on Biology and Ecology of European Orchids. Wroclaw: Wydawnictwo Uniwersytetu Wroclawskiego. 1990.