German Sourdough Bread

Luber posted a recipe for a German sourdough bread and I find it interesting.  #1 If anyone can tell me about clear flour I would love to learn and also 2)German sourdough and recipes as well.  My experience in this forum is that most people are very focused on French and Italian breads but that German breads are for the most part ignored.  Are there websites, books, and recipes that people could suggest?  Thanks..