Hi sandalss,
I already sent a comment for you a few days ago in this changeset: "https://www.openstreetmap.org/changeset/164786398", asking you about your source, without any response from you, then we edited these refs based on my available source: "https://mjla.gov.om/decisions/ar/1071/show/1188"
This is the latest version of the Oman Ministry of Transport's magazine regards numbering roads
Best regards 
Merna_mahmoud