Recommendations for resources to read, to understand HLSL?

(I understand 3D math in general; but vague on shader math and syntax - I’ve made minor changes to existing shaders over several years, but that was all in XNA 3.1 for some old DX version. I never “mastered” that old shader version.)

I know about:

Reference for HLSL - Win32 apps | Microsoft Learn

And I just found, but have not read yet:

HLSL Introduction
Effects and HLSL Tutorials - RB Whitaker's Wiki
DirectX10 Tutorial 9: The Geometry Shader | Taking Initiative