Often a good place to begin your research on a specific object is the website of the museum that owns it. Pollaiuolo's statue of Judith is owned by the Detroit Institute of Arts. Its collections database contains a bibliography of published references to this artwork (see below). A bibliography like this can give you an important place to start gathering information about your artwork.
You should contextualize your artwork in your research. Find other artworks you want to discuss in relation to it. This could mean works by the same artist, of the same subject, in the same medium, or made at the same time or place. How you choose to contextualize your artwork will establish the direction of your research.
In order to do this, pay attention to which artworks are traditionally discussed in relation to yours and think of ways to broaden this discussion. I like to search Artstor for themes to discover new works.
Search the five essential databases listed on this page for your artist and/or artwork, paying attention to variations in spelling or phrasing that could impact your search results. Don't forget that the best resources for art historical research are almost always books. Leave yourself enough time to use OhioLINK and request books from other libraries that may take several days or a week to arrive.
Image: Antonio di Jacopo Pollaiuolo (Italian, 1432-98). Judith, ca. 1470. Bronze. 42.86 cm. Detroit Institute of Arts.
To find more Italian Renaissance art in the Detroit Institute of Art or the Toledo Museum of Art, look in the following books: