"이상" biographical PDF available at LTI KOrea Library or "online". Archived from the original on September 21, 2013. Retrieved September 3, 2013.
"Yi Sang" LTI Korea Datasheet available at LTI Korea Library or "online". Archived from the original on September 21, 2013. Retrieved September 3, 2013.
"이상" biographical PDF available at LTI KOrea Library or "online". Archived from the original on September 21, 2013. Retrieved September 3, 2013.
"Yi Sang" LTI Korea Datasheet available at LTI Korea Library or "online". Archived from the original on September 21, 2013. Retrieved September 3, 2013.