APA (7th ed.) Citation

Otto Brenner Stiftung. (1998). OBS-Arbeitsheft. OBS.

Chicago Style (17th ed.) Citation

Otto Brenner Stiftung. OBS-Arbeitsheft. Frankfurt, M: OBS, 1998.

MLA (9th ed.) Citation

Otto Brenner Stiftung. OBS-Arbeitsheft. OBS, 1998.

Warning: These citations may not always be 100% accurate.