Six print volumes of the "DARE" have been published by Harvard University's Belknap Press. Volume I (1985) contains detailed introductory material, plus the letters A-C; Volume II (1991) covers the letters D-H; Volume III (1996) contains I-O; Volume IV (2002) includes P-Sk; and Volume V (2012) covers Sl-Z as well as a bibliography of nearly 13,000 sources cited in the five volumes. (Starting with Volume IV, digital libraries provided many valuable resources for expanding the historical coverage of the entries.) Volume VI (2013) includes more than 1,700 maps showing contrastive distributions of regional synonyms (such as "hero, hoagie, grinder, sub, torpedo, poor boy," and "Cuban", all of which describe a sandwich in a long bun), as well as social distributions of regional terms (by age, sex, race, education, and community type). It also includes an index to the regional, usage, and etymological labels used in the five text volumes; the text of the "DARE" Questionnaire; the responses by all "DARE" informants to 430 of the questions asked in the original fieldwork. The digital version was launched in December 2013.