Museo Hermanas Mirabal
http://www.colonialzone-dr.com/mirabal-museum.html
The website for the museum in the Dominican Republic honoring the Mirabal sisters, provides extensive information about the Mirabals, as well as a virtual tour of the museum.
Julia Alvarez: official author website
Alvarez's extensive author website provides biographical information about the author, her books, and recent news regarding interviews and appearances. The website is also updated regularly with new resources related to the subjects of her books, which can provide an excellent jumping off point for research projects based off of In the Time of the Butterflies.