APA Citation
Crookes, William,. William Crookes letter to Douglas Sladen, dated 7 Kensington Park Gardens, W., London, 5 February 1915. Retrieved from https://library.si.edu/digital-library/book/williamcrookesl00crooa
MLA Citation
Crookes, William,. William Crookes letter to Douglas Sladen, dated 7 Kensington Park Gardens, W., London, 5 February 1915. https://library.si.edu/digital-library/book/williamcrookesl00crooa
Chicago
Crookes, William,. William Crookes letter to Douglas Sladen, dated 7 Kensington Park Gardens, W., London, 5 February 1915. https://library.si.edu/digital-library/book/williamcrookesl00crooa
Warning: These citations may not always be complete (especially for serials).