APA (7th ed.) Citation

Hofmann, K. H. Semigroups and Hilbert's fifth problem.

Chicago Style (17th ed.) Citation

Hofmann, Karl H. Semigroups and Hilbert's Fifth Problem.

MLA (9th ed.) Citation

Hofmann, Karl H. Semigroups and Hilbert's Fifth Problem.

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