“The internet has changed everything” is a trite saying, but in regard to historical research it is also true. Travel and expense were often the lot of historians as they chased documents. Now, so much is available free with a few mouse clicks. Case in point is the Army series Vietnam Studies, twenty-six volumes that examine the Army’s role in Vietnam. A feast for historians or those who simply want a detailed look, for example, at Army air mobile operations in Vietnam. Each volume is now available free in PDF downloads. Go here to access them.