Revisions to Online introduction to Lattice Theory?

Update of the link; the new target has the one-file, 2017 version.

Source Link

Apart from J. B Nation's Notes on Lattice Theory Notes on Lattice Theory, is there any other (mostly introductory) material on Lattices available online?

NB: The last update of Nation's notes was 2017, as of Feb 2023.

Link update; last revision year of Nation's notes.

Source Link

Apart from J. B Nation's (revised) Notes on Lattice Theory Notes on Lattice Theory, is there any other (mostly introductory) material on Lattices available online?

NB: The last update of Nation's notes was 2017, as of Feb 2023.