APA (7th ed.) Citation

Fursiak, Y. (2013). Fast-growing sunspot groups AR1618, AR1619, AR1620, AR1640 and their features. Advances in Astronomy and Space Physics.

Chicago Style (17th ed.) Citation

Fursiak, Yu.A. "Fast-growing Sunspot Groups AR1618, AR1619, AR1620, AR1640 and Their Features." Advances in Astronomy and Space Physics 2013.

MLA (8th ed.) Citation

Fursiak, Yu.A. "Fast-growing Sunspot Groups AR1618, AR1619, AR1620, AR1640 and Their Features." Advances in Astronomy and Space Physics, 2013.

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