here is a book that has correspondence and other data to back that theory:http://www.amazon.com/Becoming-Laura-Ingalls-Wilder-BIOGRAPHY/dp/082621648X/ref=sr_1_1?ie=UTF8&qid=1357044447&sr=8-1&keywords=becoming+laura+ingalls+wilderCollections of the articles that Laura wrote for The Missouri Ruralist are available and definitely show her writing ability.