APA (7th ed.) Citation

Hetmaniok, E., Pleszczyński, M., Sobstyl, I., & Wituła, R. Kaprekar's transformations. Part I—theoretical discussion. Polish Information Processing Society.

Chicago Style (17th ed.) Citation

Hetmaniok, Edyta, Mariusz Pleszczyński, Ireneusz Sobstyl, and Roman Wituła. Kaprekar's Transformations. Part I—theoretical Discussion. Polish Information Processing Society.

MLA (9th ed.) Citation

Hetmaniok, Edyta, et al. Kaprekar's Transformations. Part I—theoretical Discussion. Polish Information Processing Society.