I own copies of the following books on the role of the 5th Army in Italy. They belonged to my father. They are too long to post, but here are links where you can read them Lone Sentry: 5th Army Antiaircraft, Salerno to Florence, 9 September 1943 - 8 September 1944, WWII Unit History Stars and Stripes "Puptent Poets" (poetry by soldiers in the Mediterranean) SALERNO: American Operations From the Beaches to the Volturno 9 September - 6 October 1943 (my cover is different. It's the original 1944 version) I also have a book entitled Road to Rome which is a more general look at the 5th Army's engagements. It is signed by my father, since he sent it home to my mother.
Interesting - my father served in the Fifth Army from Anzio to Rome. His unit - a British artillery unit - was equipped with M7 Priests so it could be resupplied easily under a US command. Thanks for those links.