Indeks judul : opac usu library, Opac usu library. library catalog, covers holdings university library systems including main library branches..
http://digilib.usu.ac.id/indexing/M.html
Kisi info indonesia abad 19(bersambung, Koleksi sejarah indonesia abad 19 bagian keempat oleh dr iwan suwandy , mha edisi pribadi terbatas khusus kolektor historian senior copyright.
https://driwancybermuseum.wordpress.com/2013/10/21/koleksi-sejarah-indonesia-abad-19bersambung/