@inproceedings{mci/Heller1972,
author = {Heller, Ehrenfried},
title = {Siemens-System 300 für Prozeßautomatisierung, Band 1: Zentraleinheiten},
booktitle = {},
year = {1972},
editor = {},
publisher = {Siemens Aktiengesellschaft},
address = {Berlin und München}
}