Leonard Eugene Dickson (January 22, 1874 – January 17, 1954) was an American mathematician. He was one of the first American researchers in abstract algebra, in particular the theory of finite fields and classical groups, and is also remembered for a three-volume history of number theory, History of the Theory of Numbers.
Even though the book is labeled "First Course..", I found it too basic. Neither is the prose good, questions good nor the content is rigorous enough. Had to go through, because it was the recommended reading in my college.