Sister Wendy. Beware of Sister Wendy. I use her as a point to start the conversation with the students on art history. She is not an expert and while she admits that, kids can be confused as to her 'autheticity in knowledge'. I have her video tapes and her books, and my AP Art History students delighted in challenging her as their knowledge grew. She does however, have great access to wonderful pieces of artwork without anyone else in the room. If you watch the tapes as many times as my students and I have, however, you begin to wonder about Sister Wendy in many ways.
San D
The only way I can think of to find out is to ask an art historian from the Catholic Church. There was a syndicated PBS show a few years ago and some books printed about a nun (I can't remember her name) who did not claim to be an art historian just someone who liked art. She may have a website. Or perhaps others remember her. JNO