The International Standard Book Number (ISBN) is a numeric book identifier that is intended to be unique. The number can be different for each version / edition as well as types (digital and physical). For physical, we use the ISBN number which is usually at the back of the book while for digital copies such as ebooks, we use eISBN.

Source : https://en.wikipedia.org/wiki/ISBN

Source : https://en.wikipedia.org/wiki/ISBN
ISBN and ISSN can be applied directly from Malaysia National Library (PNM) through Depositori System.

https://depositori.pnm.gov.my/

https://depositori.pnm.gov.my/