Complex sentence: Adrienne von Speyr (20 September 1902-17 September 1967) was a Swiss Catholic medical doctor, the author of over 60 books of spirituality and theology, and a mystic and stigmatist.
Split into simpler sentences: Adrienne von Speyr (20 September 1902-17 September 1967) was a Swiss Catholic physician, writer and theologian. She was the author of over 60 books of spirituality and theology, and a mystic and stigmatist.