In a time of rampant historical revisionism, Walter Lords 1961 book "A Time to Stand" is still the standard by which all other books on the Alamo is measured. He managed to write an account of the events surrounding the battle at the Alamo in an academically succinct manor yet the text easily captures the casual reader. For the more serious student of Texas history the details and sources are well documented in the source notes at the end of the book.
A few years ago while visiting the Alamo I was in the gift shop. A Swedish tourist was browsing through the numerous books available that chronicles the events at the Alamo in those fateful days in March of 1836. Being Texas "friendly" I started a conversation with this gentleman about his book selection. I told him that you could have only one book on the Alamo, I recommend, "A Time to Stand".
Texas Bob