Disquisitio philologico-physica De magnete / quam Deo Sospitante Inclyta Facult. Philosophica permittente Præses M. Nicolaus Klein/ Colmaria-Alsatus, SS.Th.Stud. & Respondens Johannes Fridericus Keßler/Themarâ, Phil. Bacc.. &Ser.El. Sax. Alumnus Publico placidoq[ue] Eruditorum Examini submitunt in Almâ Lipsiensi, ad diem XV Mens. Decembr. anno MDC. LX H.L.Q.C. Lipsiæ : Typis Johannis Baueri, [ante 15 XII 1660]