The below list of reference books and magazines/journals which I have used to collect data and history on ships in my collection. These are sources which I have acquired or have used at local libraries. They are ranked in importance from most to least useful for my collection of postcards. There are often contradictions between references on specifications of warships such as displacement. I strongly recommend using the Dictionary of American Naval Fighting Ships and any book published by Conways. The Illustrated Encyclopedia is good on general history for many ships.