A similar situation exists with regard to musical ontology, though primary focus is given to works of classical music in some instances. One ontological issue pertaining centrally to classical music concerns the metaphysical nature of a work of music. Do musical works exist? If so, in what sense? With regard to musical ontology a Platonist would hold that a work of classical music is an abstract object, while a nominalist would hold that it must be understood solely in terms of particular objects that relate to it, such as the musical score. In contrast to all of these, anti-realists deny that musical works have any kind of real existence at all, though stopping short of discounting the question altogether, some anti-realists grant musical works a fictional status.
In 2001, Harvard University Press began issuing a second series of books with a similar format. The I Tatti Renaissance Library presents key Renaissance works in Latin with a facing English translation; it is bound similarly to the Loeb Classics, but in a larger format and with blue covers. A third series, the Dumbarton Oaks Medieval Library , was introduced in 2010 covering works in Byzantine Greek, Medieval Latin, and Old English. Volumes have the same format as the I Tatti series, but with a brown cover. The Clay Sanskrit Library , bound in teal cloth, was also modeled on the Loeb Classical Library.