An Introduction to Probability Theory and Its Applications, Volume 2, 2nd Edition
https://www.wiley.com/en-us/An+Introduction+to+Probability+Theory+and+Its+Applications%2C+Volume+2%2C+2nd+Edition-p-9780471257097
An Introduction to Probability Theory and Its Applications, Volume 1, 3rd Edition
https://www.wiley.com/en-us/An+Introduction+to+Probability+Theory+and+Its+Applications%2C+Volume+1%2C+3rd+Edition-p-9780471257080