Quoted by NPR http://www.npr.org/2016/10/28/499796182/british-comedian-tracey-ullman-brings-celebrity-impersonations-to-hbo in 2016, on what what drives her to do impersonations
Tracey Ullman: Doing
Tracey Ullman is English-born actress, comedian, singer, dancer, screenwriter, producer, director, author and businesswoman. Explore interesting quotes on doing.The Des Moines Register https://www.newspapers.com/image/296428181 (11 May 1990)
On playing multiple characters in her television shows
"Ullman, By Hook & By 'Crooks'" http://www.nydailynews.com/ullman-hook-crooks-tracey-tireless-efforts-landed-role-woody-allen-leading-lady-article-1.859726 (NY Daily News, 14 May 2000)
Quoted in 1989 in The New York Times article "Tracy Ullman Makes A Face" http://www.nytimes.com/1989/10/15/magazine/tracy-ullman-makes-a-face.html?pagewanted=all
Tracey Ullman: Live and Exposed (2005)
Quoted in 2016 in The Guardian https://www.theguardian.com/culture/2016/jan/10/tracey-ullman-my-face-is-good-for-impersonations
"Tracking Tracey" http://www.dareland.com/emulsionalproblems/ullman.htm (Interview, January 1989)