I have taken the liberty of standardizing Ellen Gould Harmon White's name as Ellen G. White because that seems to be the most common form. It is used by her grandson in his biography of her, on what purports to be her official website, and in Wikipedia.
Ellen Gould White (born Harmon) (November 26, 1827 – July 16, 1915) was a prolific author and an American Christian pioneer. She, along with other Sabbatarian Adventist leaders, such as Joseph Bates and her husband James White, would form what is now known as the Seventh-day Adventist Church. She was also commonly referred to as Sister White.Ellen G. White in Wikipedia