The Philippi headwear collection is currently the world’s largest
collection of clerical, ecclesiastical and religious head coverings
and is unique in both its scope and size. You will find examples of headgear from every religious persuasion around the globe, whether ceremonial or worn as part of everyday life. In addition, the collection includes 116 religious objects.
December 08, 2010
My Kingdom for a Crown: The Religious Skullcap, Publish America, 2004, ISBN 1413705383
If you want to know all about the skullcap maybe this book would be fine as Christmas reading?