It seems that I can't get enough from these very Austrian mystery novels at the moment, having finished "Der Frauenmörder" [The ripper] in January. Not so much because of their (debatable) literary quality - I like that Bettauer always transports social problems like unemployment, malnutrition, battlefield injuries, lung diseases, and he probably was far ahead of his time, as far as sexual morals are concerned, e.g. when he talks about prostitution [one of the main characters in "Die freudlose Gasse" expresses understanding for the young women who prostitute themselves because they and their families have nothing to eat and there's no hope for change. He criticises not the prostitutes, but the punters and panders exploiting their distress]. So these works are excellent depictions of the society of Bettauer's time even more than they are mystery stories, although there is murder, and theft, and procuration, and general inmorality ;-) And, simply, they are page-turners. I think it helps if you are familiar with Vienna and/or Austrian history. - Sometimes though I think the bad guys come away too easily.