The increase in women's rights of the early 1900s led to the first Puerto Rican women to work in positions traditionally occupied by men, including the first medical practitioners in the island. Drs. María Elisa Rivera Díaz and Ana Janer started their practices in 1909 and Dr. Palmira Gatell in 1910.[45] Ana Janer and María Elisa Rivera Díaz graduated in the same medical school class in 1909 and thus could both be considered the first female Puerto Rican physician.[46] These two and Palmira Gatell were followed by Dr. Dolores Mercedes Piñero, who earned her medical degree from the College of Physicians and Surgeons in Boston in 1913.[47] In 1914, Rosa A. González earned a degree in nursing, established various health clinics throughout Puerto Rico and was the founder of The Association of Registered Nurses of Puerto Rico. González authored two books related to her field in which she denounced the discrimination against women and nurses in Puerto Rico.