Can you people please post a scientific source for the definition of Aryan?

Ignoring the truth doesn't change it.

https://books.google.co.uk/books?id=96sQAAAAIAAJ&source=gbs_navlinks_sThe Aryan Origin of the Gaelic Race and Language
Ulick Joseph Bourke


In another words, Aryans are the descendants of people which lived in the European continent, British Islands, Iceland and west Russia before 20th century.