- Author: Robert Morstein-Marx
- Language: English
- Year: 2004
- Author: Robert F. Marx
- Language: English
- Year: 2023
- Author: Robert F. Marx
- Language: English
- Year: 1967
- Author: Robert Kallet–marx
- Language: English
- Year: 1996
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- Language: English
- Year: 2021
- Author: Robert E. Marx
- Language: English
- Year: 2022
- Author: Robert Morstein-Marx
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- Year: 2021
- Author: Robert E Marx
- Language: English
- Year: 2017