Update week4.do.txt

Author: mhjensen

doc/src/week4/week4.do.txt

@@ -11,6 +11,10 @@ o Simple Hamiltonian systems
 o "Video of lecture to be added":"https://youtu.be/"
 #o "Whiteboard notes":"https://github.com/CompPhysics/QuantumComputingMachineLearning/blob/gh-pages/doc/HandWrittenNotes/2025/NotesFebruary12.pdf"
 
+!split
+===== Readings =====
+
+o For the discussion of one-qubit, two-qubit and other gates, sections 2.6-2.11 and 3.1-3.4 of Hundt's book _Quantum Computing for Programmers_, contain most of the relevant information. 
 
 
 !split