An online civic group that promotes correct understanding of Korean history and culture has found that many top English-language dictionaries and encyclopedias did not contain entries on the ancient Korean kingdoms of Goguryeo or Balhae.

The Voluntary Agency Network of Korea, or VANK, said on Tuesday that it searched for the two kingdoms in 14 reference works used by teenagers worldwide, including Merriam-Webster, the Oxford English Dictionary and YourDictionary.

The organization found that Goguryeo was only mentioned in Wordnik, Wikipedia and YourDictionary, with all three describing Goguryeo as an ancient kingdom of the Korean Peninsula.

Balhae, however, was only logged on Wikipedia and was wrongly referred to as “the subject of a historiographical dispute between Korea, China and Russia.”

VANK stressed the need to correct inaccurate information and include the two Korean kingdoms in future editions, saying these are ways to confront China’s attempts to distort history.