Il fiume dell’orrore

Along the course of the Armanack, towards Witch’s Gorge and Desolate Valley, the one-time dwelling place of the witch Asenath Prynn. This, indeed, is the risky itinerary followed by Harlan in his endeavor to get to the heart of the mystery about the curse those lands are under, where the descendants of ancient witch hunters live in the wilds in abject wretchedness. For amid the deep forests, nothing is as it should be: neither the trees, nor the animals, nor the members of the monstrous Pickering family…

In Dampyr 37 shows Marvin (mistakenly called "Martin" in a cartoon), Torricelli the designer has deliberately designed him with the features of a young Martin Mystere. 
Not only that, but Martin Mystère is explicitly mentioned.