The first three titles are large multivolume sets; they are the most comprehensive and scholarly dictionaries of artists. Many obscure artists who are not included in other encyclopedias can be found in them. The International Dictionary of Art and Artists covers far fewer artists; however, its second volume, which contains one-page articles on individual works of art, can help you get a good start researching specific art works.
This one-volume encyclopedia concentrates on European and American painters of the nineteenth century. It is especially useful for its articles on, and reproductions of representative paintings by, lesser-known artists.
These books provide an excellent start when doing research on women artists in a wide variety of media. The second one offers substantial articles on women artists from the Middle Ages to the present day.