APA (7th ed.) Citation

Quirrenbach, A. (1991). Intraday variability of extragalactic radio sources. Variability of active galactic nuclei.

Chicago Style (17th ed.) Citation

Quirrenbach, Andreas. "Intraday Variability of Extragalactic Radio Sources." Variability of Active Galactic Nuclei 1991.

MLA (9th ed.) Citation

Quirrenbach, Andreas. "Intraday Variability of Extragalactic Radio Sources." Variability of Active Galactic Nuclei, 1991.

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