diff --git a/README.org b/README.org
index bf089ab..ab83026 100644
--- a/README.org
+++ b/README.org
@@ -38,3 +38,18 @@ Or
 ** Libraries
 
 - [[https://github.com/riyyi/ruc][ruc]]
+
+** References
+
+*** Test ROMs
+
+https://github.com/gbdev/awesome-gbdev#testing
+https://tasvideos.org/EmulatorResources/GBAccuracyTests
+
+*** Opcodes
+
+https://www.pastraiser.com/cpu/gameboy/gameboy_opcodes.html
+https://github.com/lmmendes/game-boy-opcodes
+
+https://rgbds.gbdev.io/docs/v0.5.2/gbz80.7/
+https://gbdev.io/pandocs/CPU_Instruction_Set.html