Anna Riva (1923–2005) was the pen name of Dorothy Spencer, who was a well-known American occult author and manufacturer of hoodoo spiritual supplies. According to Catherine Yronwode, "Anna Riva" was a nom de plume that this author used only in her writing and business; Anna was her mother's name and Riva was her daughter's name.
In Spiritual Merchants, Carolyn Morro Long described how the "1970s and 1980s saw the publication of a new crop of spell books" for products available from the same companies selling the books. "The best-known of these writers is the extremely prolific Dorothy Spencer, who writes under the name 'Anna Riva.'
When Spencer retired in the late 1990s, her company, International Imports of Los Angeles, was purchased by Indio Products. The owner of Indio Products, Marty Meyer, stated that the woman known as Anna Riva was suffering from Alzheimer's disease in 2000. In Spiritual Merchants (2001), Carolyn Long wrote "Dorothy Spencer is now quite elderly and, unfortunately, suffers from Alzheimer's disease, so I was unable to interview her.
Anna Riva's magical oils, incenses and powders are sold by numerous occult suppliers, along with her books.