found: CIA World Factbook online:(country: Guatemala; nationality: Guatemalan(s))
found: Dickson, P. Labels for locals, 2006(Guatemala (Republic of Guatemala): Guatemalan)
found: IPUMS ancestry code conversions 1990 ancestry codes, via WWW, Mar. 30, 2016(Guatemalan (Guatemala, Guatamalteca, Guatemalteco))
found: Names of countries and their capital cities including adjectives of nationality and currency units, 2001(Guatemala. Adjective of nationality: Guatemalan (English), guatemalteco (Spanish))
found: 98222571: La cultura democrática de los guatemaltecos, 1998.