APA (7th ed.) Citation

Engels, F., Lafargue, L., & Lafargue, P. Religion, philosophie, socialisme. G. Jacques (Paris).

Chicago Style (17th ed.) Citation

Engels, Friedrich, Laura Lafargue, and Paul Lafargue. Religion, Philosophie, Socialisme. G. Jacques (Paris).

MLA (8th ed.) Citation

Engels, Friedrich, et al. Religion, Philosophie, Socialisme. G. Jacques (Paris).

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