Kim, Tae Gon
Gugo ohwi ui thongsijok yongu
Bogjong, 2008
 Buku Teks
Guko saenghwal
by Lee Sam Hyong ... [and others]
Joongang kyoyook jin heung yeongooso, 2003
 Buku Teks
Lee, Ki-mun
Donga sae guko sajon
Seoul Doosan Dong a, 2003
 Buku Referensi
Nam, Gi-sim
Hyeondae Guko thongsaron
Thaehaksa, 2010
 Buku Teks
Lee, Jin-ho
Guko umun kyoyuk pyonchonsa
Pagijong Press, 2009
 Buku Teks