Herschel, William (6 May 1802). "Observations on the two lately discovered celestial Bodies". Philosophical Transactions of the Royal Society of London. 92: 213–232. doi:10.1098/rstl.1802.0010. JSTOR107120.
Herschel, William (6 May 1802). "Observations on the two lately discovered celestial Bodies". Philosophical Transactions of the Royal Society of London. 92: 213–232. doi:10.1098/rstl.1802.0010. JSTOR107120.