Amongst other research, the Kemps gained information through correspondence with several friends of the Haders, such as J. J. Marquis, Jane Terrill Barrow, Ruth and Latrobe Carroll, and Doris Patee.
In addition to their work, the Kemps collected data through communications with some of the Haders' acquaintances, such as J. J. Marquis, Jane Terrill Barrow, Ruth and Latrobe Carroll, and Doris Patee.