APA (7th ed.) Citation

Sladkov, N., & Altschuler, H. A topsy-Turvy planet. Moscow Progress.

Chicago Style (17th ed.) Citation

Sladkov, N., and Helen Altschuler. A Topsy-Turvy Planet. Moscow: Moscow Progress.

MLA (9th ed.) Citation

Sladkov, N., and Helen Altschuler. A Topsy-Turvy Planet. Moscow Progress.

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