diff --git a/src/backend/core/mmio/AI.cpp b/src/backend/core/mmio/AI.cpp
index a29fbc76..e2b3652e 100644
--- a/src/backend/core/mmio/AI.cpp
+++ b/src/backend/core/mmio/AI.cpp
@@ -17,6 +17,8 @@ void AI::Reset() {
   dac = {44100, N64_CPU_FREQ / dac.freq, 16};
 }
 
+// https://github.com/ares-emulator/ares/blob/master/ares/n64/ai/io.cpp
+// https://github.com/ares-emulator/ares/blob/master/LICENSE
 auto AI::Read(u32 addr) const -> u32 {
   if(addr == 0x0450000C) {
     u32 val = 0;
diff --git a/src/backend/core/mmio/PIF.hpp b/src/backend/core/mmio/PIF.hpp
index f5637b35..77f052e8 100644
--- a/src/backend/core/mmio/PIF.hpp
+++ b/src/backend/core/mmio/PIF.hpp
@@ -81,6 +81,8 @@ struct JoybusDevice {
 struct Mem;
 struct Registers;
 
+// https://github.com/ares-emulator/ares/blob/master/ares/n64/cic/cic.cpp
+// https://github.com/ares-emulator/ares/blob/master/LICENSE
 constexpr u32 cicSeeds[] = {
   0x0,
   0x00043F3F, // CIC_NUS_6101