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
Nam, Ki-sim
Pyojun guko munpomnon
Topchulpansa, 2010
Buku Teks
Nam, Gi-sim
Hyeondae Guko thongsaron
Thaehaksa, 2010
Buku Teks
Lee, Jin-ho
Guko umun kyoyuk pyonchonsa
Pagijong Press, 2009
Buku Teks