Richards, Joan L. Department Ideals and Practices of Rationality, Max Planck Institute for the History of Science, Max Planck Society;
Hobart, M. E., & Richards, J. L. (2008). De Morgan's logic. In J., Woods, & D. M., Gabbay (Eds.), British logic in the nineteenth century (pp. 283-329). Amsterdam [u.a.]: North-Holland.