Heat Transfer was one of my worst classes, and my least favorite in my junior year. There are numerous engineer handbooks that have distilled info on heat transfer (in part), plus the classical treatements at various levels. In graduate school, I had to do a lot of research on various things, and that was long before the era of the Internet and easy accesss to east coast reference material (I was in the south). Any university these days should have a decnet library I would think. Both my undergraduate and graduate engineering schools maintained their own technical reference library. These are how I'd research material needed for a Doctoral Dissertation.
BTW, A thesis is for a Master's Degree, and the difference is that a Thesis need not be original thought; a Dissertation must contribute new thought significant to the field of endeavor. A Thesis can simply rehash the work of others; Disertations cannot (well, they are not supposed to, but some schools are sloppy or of low reputation).