APA (7th ed.) Citation

Heidt, J., Wagner, S., & Erkens, U. (1991). Optical monitoring of southern BL Lac-objects. Abstract series, 6, .

Chicago Style (17th ed.) Citation

Heidt, Jochen, Stefan Wagner, and Ulrike Erkens. "Optical Monitoring of Southern BL Lac-objects." Abstract Series 6 (1991).

MLA (9th ed.) Citation

Heidt, Jochen, et al. "Optical Monitoring of Southern BL Lac-objects." Abstract Series, vol. 6, 1991.