Theresa Dyer, better known by her pen names, Minnie Myrtle and Minnie Myrtle Miller (May 2, 1842 – May 15, 1882), was an American author of prose and verse. She was a frequent contributor to the newspapers under her pen name, "Minnie Myrtle" before her marriage to Joaquin Miller, and "Minnie Myrtle Miller" thereafter.