Where does “Дойлеров” come from?

Дойлеров (Bulgarian) comes from Romanian doilea, from Romanian doi, from Vulgar Latin dui, from Latin duō, from Proto-Italic duō, from Proto-Indo-European dwóh₁ — two.

Ancestry of “Дойлеров”, step by step

Step	Language	Word	Meaning
1	Romanian	doilea	second
2	Romanian	doi	two
3	Vulgar Latin	dui	two
4	Latin	duō	two; 2
5	Proto-Italic	duō	two
6	Proto-Indo-European	dwóh₁	two

Every word from Proto-Indo-European dwóh₁ →Every word from Proto-Italic duō →Every word from Latin duō →