Walthall, 2014, [1], p. 171, en Google Libros: "In the case of the Khitan Liao, two decades of military confrontation ended in 1020 with a negotiated settlement to transfer Goryeo’s vassal status from the Song to the Liao." "Liao forces invaded Goryeo territory in 993. ... the Khitans negotiated a peace that forced Goryeo to adopt the Liao calendar and end tributary relations with Song ... In 1010, on the pretext that the rightful king had been deposed without the approval of the Liao court, the Khitan emperor personally led an attack that culminated in the burning of the Goryeo capital. Several other confrontations followed until Goryeo reaffirmed its tributary relationship with Liao in 1020."
Yun, 1998, p.64: "By the end of the negotiation, Sô Hûi had ... ostensibly for the purpose of securing safe diplomatic passage, obtained an explicit Khitan consent to incorporate the land between the Ch’ôngch’ôn and Amnok Rivers into Koryô territory." Yun, Peter I. (1998), Rethinking the Tribute System: Korean States and northeast Asian Interstate Relations, 600-1600 (Thesis (Ph.D.)), University of California, Los Angeles..
Walthall, 2014, [2], p. 171, en Google Libros: "In 1010, on the pretext that the rightful king had been deposed without the approval of the Liao court, the Khitan emperor personally led an attack that culminated in the burning of the Goryeo capital."
Ebrey y Walthall, 2014, [3], p. 179, en Google Libros. "The Mongols made sure the Korean kings knew who was in charge. Mongol emperors deposed Goryeo kings who failed to serve their interests in 1298, 1313, 1321, 1330, 1332, 1343, and 1351. Some kings were held in detention in Dadu (Beijing) to issue decrees in absentia. Insult was added to injury in 1343 when Mongol envoys arrested the Korean king for initiating reforms detrimental to Mongol interests. They kicked him around, tied him up, and exiled him to China, but he died on the way". Ebrey, Patricia Buckley; Walthall, Anne (2014), Pre-Modern East Asia: To 1800: A Cultural, Social, and Political History, Third Edition, Boston, MA: Wadsworth, Cengage Learning, ISBN978-1-133-60651-2..
Ebrey y Walthall, 2014, [4], p. 171, en Google Libros: "In the case of the Jurchen Jin, the [Goryeo] court decided to transfer its tributary relationship from the Liao to Jin before serious violence broke out." Also p.172: "Koryŏ enrolled as a Jin tributary". Ebrey, Patricia Buckley; Walthall, Anne (2014), Pre-Modern East Asia: To 1800: A Cultural, Social, and Political History, Third Edition, Boston, MA: Wadsworth, Cengage Learning, ISBN978-1-133-60651-2..
Seung B. Kye (2021). «12. Slavery in Medieval Korea». En Craig Perry; David Eltis; Stanley L. Engerman et al., eds. The Cambridge World History of Slavery, Vol. II: AD 500–AD 1420(en inglés). Cambridge University Press. p. 297. ISBN9781139024723. doi:10.1017/9781139024723. «the heritability of slave status was enacted as evidenced by the Matrilineal Succession Law (chongmopŏp) of 1036, which stated that the offspring of nobi shall inherit the status of the mother».Se sugiere usar |número-editores= (ayuda)
Hyun, 2013, p.106: "Even though the Goryeo court agreed to set up tribute exchanges with the Liao court, that same year [=994] it also sent an envoy to the Song court to appeal, but in vain, for military assistance against the Khitan." Hyun, Jeongwon (2013), Gift Exchange among States in East Asia during the Eleventh Century (Thesis (Ph.D.)), University of Washington..
Hyun, 2013, p.3: "The Goryeo ... sent tributary missions to the Later Tang, Later Jin, Later Han and Later Zhou successively, which Goryeo officials recognized as proper successors of the Tang, the new "centers" of China." Hyun, Jeongwon (2013), Gift Exchange among States in East Asia during the Eleventh Century (Thesis (Ph.D.)), University of Washington..
