[https://www.g-rau.de/en/company/history.html], [https://www.fountainpennetwork.com/forum/topic/351328-interesting-looking-nib-on-vintage-omas-extra-lever-filler/] | [https://www.g-rau.de/en/company/history.html], [https://www.fountainpennetwork.com/forum/topic/351328-interesting-looking-nib-on-vintage-omas-extra-lever-filler/] |