Ethnohistory is the study of cultures and indigenous peoples customs by examining historical records as well as other sources of information on their lives and history. It is also the study of the history of various ethnic groups that may or may not still exist. The term is most commonly used in writing about the history of the Americas. Ethnohistory uses both historical and ethnographic data as its foundation. Its historical methods and materials go beyond the standard use of documents and manuscripts. Practitioners recognize the use of such source material as maps, music, paintings, photography, folklore, oral tradition, site exploration, archaeological materials, museum collections, enduring customs, language, and placenames. Scholars studying the history of Mexico's indigenous have a long tradition, dating back to the colonial era; they used alphabetic texts and other sources to write the history of Mexico's indigenous peoples. The Handbook of Middle American Indians, edited by archeologist Robert Wauchope was involved with creating a multiple volumes on Mesoamerican ethnohistory, published as Guide to Ethnohistorical Sources, appearing in 1973. At the time that the volumes were published, "both the term 'ethnohistory' and its concepts in the sense used here have entered the literature rather recently and are not fully agreed upon." The volumes were intended to be an inventory of sources "which in later hands could utilize to produce professionally acceptable ethnohistory." In the mid to late 20th century, a number of ethnohistorians of Mexico began to systematically publish many colonial alphabetic texts in indigenous Mexican languages, in a branch of ethnohistory currently known as the New Philology. That built on an earlier tradition of practitioners writing the history of Mexico that fully integrated the history of its indigenous peoples. In the United States, the field arose out of the study of American Indian communities required by the Indian Claims Commission.