Brown, Delmer (1948). »The Impact of Firearms on Japanese Warfare, 1543-1598«. Far Eastern Quarterly. 7 (3): 236–253. doi:10.2307/2048846. JSTOR2048846.
jstor.org
Brown, Delmer (1948). »The Impact of Firearms on Japanese Warfare, 1543-1598«. Far Eastern Quarterly. 7 (3): 236–253. doi:10.2307/2048846. JSTOR2048846.
unesco.org
whc.unesco.org
Gusuku Sites and Related Properties of the Kingdom of Ryukyu [1]