Catherine Ponder
and
Randy Gage

If you're looking for materials to help you develop a prosperous mindset, then these are two of the best I've read so far. Catherine Ponders' book goes in depth about the different laws of prosperity and quotes many passages from the bible to bring home each section. Originally published in 1962, this is another classic and must have. Whether you read the Bible or not, this book will impress any reader.

Randy Gage writes about prosperity in a straightforward manner. He refers to the Ponder book and many others throughout his material. You can tell he has studied prosperity thinking in depth.

If you're not an avid reader, you may want to opt for the Randy Gage material as it is much shorter than Ponders', but still has great strength to it. I would still recommend picking up the Ponder book though. It is truly a great reference book.