HC
H. Emilie Cady
Harriet Emilie Cady was an American homeopathic physician and author of New Thought spiritual writings. Her 1896 book Lessons in Truth: A Course of Twelve Lessons in Practical Christianity is now considered one of the core texts on Unity Church teachings. It has sold over 1.6 million copies since its first publication.
Excerpt from Wikipedia, available under CC BY-SA 4.0.
Books

Lessons in Truth
2003
ISBN 9780871592859
God a Present Help
2023
ISBN 9781019392928