As you only require one reference, I will present K.S. Krane, Introductory Nuclear Physics, section 14.5 "Thermonuclear Weapons." The relevant schematic is numbered 14.19. I chose this because it's a textbook that I remember using myself; I'm not sure what is usually used these days.
But I dug up the diagram you mentioned just because I was curious.
https://archive.org/details/introductory-nuclear-physics/pag...
Seems pretty different from the image in the linked post.
I don't believe either of them are actually representative of a function warhead; see for instance https://images.app.goo.gl/aEBGKmAb8NsoAWe87, which suggests that in a real design the primary and secondary are inverted compared to the image shown in the blog post.