倫理学原理
Bell, Clive (1973). “Old Friends”. Civilization and Old Friends. University of Chicago Press. ISBN 0-226-04206-5. OCLC 963209. https://archive.org/details/civilizationoldf00bell
The Bloomsbury Group: A Collection of Memoirs and Commentary. University of Toronto Press. (1995). ISBN 978-1-4875-7376-8. OCLC 1085567888. https://archive.org/details/bloomsburygroup00rose_0