Here are some, mostly improvable, idl sources eventually useful for others. Any comments, corrections hints should be directed to karo13de at googlemail.com. Many hints are taken from the idl community, especially from David Fannings pages and from the idl news list comp.lang.idl-pvwave. Missing references should be excused gratiously. If the idl sources are not legible under the WWW browser, save them and view under idlde.