Contraction groups and passage to subgroups and quotients for endomorphisms of totally disconnected locally compact groups
T.P. Bywaters, H. Glöckner, S. Tornier, Israel Journal of Mathematics 227 (2018) 691–752.

Real and p-adic Lie algebra functors on the category of topological groups.
H. Glöckner, Pacific Journal of Mathematics 203 (2002) 321–368.