The most extensive source of information about Helen is Without Wings the Way Is Steep: the Autobiography of Sybil Shearer, Volume II, The Midwest Inheritance, published in 2012. Sybil writes about Helen throughout this volume, which also includes numerous letters written from Helen to Sybil during the summers of 1943-1950 when Sybil was at home with her parents in Lyons, New York.
Other sources of information include endorsements and inscriptions by notable subjects; information on Helen’s portraits owned by other museums and collectors; and anecdotes in oral histories relating to Sybil Shearer.