Who wrote the first book on the topic of school psychology in 1930?

Known to be a psychologist at Lincoln School at Teacher’s College, Columbia then after at Brooklyn College at New York, Gertrude Hildreth authored so many books. Included in these books is the first book pertaining to school psychology titled, "Psychological Service for School Problems". This was written by Hildreth in the year 1930. If one will read this book, one will read discussions about applying the science of psychology to address the perceived problems in schools. The objective of the book is to let the readers know about the applied educational psychology to improve learning outcomes. This was what Ms. Gertrude wrote about as the main focus of the book.