I have come across some occurrences of 'Dr. Th.' followed by a name. I first thought it means Doctor theologiae, but I am seeing it in contexts that have nothing to do with theology.
Betriebswirtschaftlicher Verlag Dr. Th. Gabler, Gablers Wirtschafts-Lexikon, Band 3, 1984, Sp. 2161
Is 'Th.' by any chance the short form of Theodor?