Help translating Military abbreviation written in Sütterlin

[twfmd]

I recently acquired a Reibert infantry manual with the former owner's surname (which appears to be "Düljas") followed by a military abbreviation and "I.R." for Infanterie Regiment. If anyone can decipher the abbreviation I would be appreciative.
Thanks.
Tom

Reibert 1943 Inscription.JPG (137.42 KiB) Viewed 5350 times

[GregSingh]

I read surname as: Dulias, and abbreviation as: Hptm. d. R. - could be Hauptmann der Reserve.

[twfmd]

Thank you very much Greg! I appreciate it.
Regards,
Tom