What type of source is the following citation?
Di Cosmo, Nicola, Allen J. Frank, and Peter B. Golden, eds. The Cambridge History of Inner Asia: The Chinggisid Age. Cambridge, UK: Cambridge University Press, 2009.
What type of source is the following citation:
Biran, M. The Battle of Herat (1270): A case of inter-Mongol warfare. In Di Cosmo, Warfare in Inner Asian History (500-1800) (Leiden, 2002), 175-219.
Jackson, P. The crusade against the Mongols (1214). Journal of Ecclesiastical History 42/1 (1991), 1-18.