x86 asm readme: link to LOCK answers

Author: cirosantilli

README.adoc

@@ -13128,12 +13128,17 @@ TODO We didn't manage to find a working ARM analogue to <<x86-rdtsc-instruction>
 
 === x86 LOCK prefix
 
-Ensures that memory modifications are visible across all CPUs, which is fundamental for thread synchronization.
-
 Inline assembly example at: link:userland/cpp/atomic.cpp[]
 
+Ensures that memory modifications are visible across all CPUs, which is fundamental for thread synchronization.
+
 Apparently already automatically implied by some of the <<x86-exchange-instructions>>
 
+Bibliography:
+
+* https://stackoverflow.com/questions/8891067/what-does-the-lock-instruction-mean-in-x86-assembly/56803909#56803909
+* https://stackoverflow.com/questions/980999/what-does-multicore-assembly-language-look-like/33651438#33651438
+
 === x86 assembly bibliography
 
 ==== x86 official bibliography