@article{2006:lohrmann:idee_und_w,
title = {Idee und Wirklichkeit des Perpetuum mobile im Mittelalter},
year = {2006},
note = {},
journal = {TG Technikgeschichte},
pages = {227--252},
author = {Lohrmann, Dietrich},
volume = {73},
number = {3-4}
}