APA
Ryser S., Weber M. & Drews J. (1991). Genetic engineering ¿what happening at Roche?. Basel: Editiones Roche.
Chicago
Ryser Stefan, Weber Marcel and Drews Jürgen. 1991. Genetic engineering ¿what happening at Roche?. Basel: Editiones Roche.
Harvard
Ryser S., Weber M. and Drews J. (1991). Genetic engineering ¿what happening at Roche?. Basel: Editiones Roche.
MLA
Ryser Stefan, Weber Marcel and Drews Jürgen. Genetic engineering ¿what happening at Roche?. Basel: Editiones Roche. 1991.