Non-Lie subgroups in Lie groups over local fields of positive characteristic
H. Glöckner, P-Adic Numbers, Ultrametric Analysis, and Applications 14 (2022) 138–144.

Exponential laws for ultrametric partially differentiable functions and applications
H. Glöckner, P-Adic Numbers, Ultrametric Analysis and Applications 5 (2013) 122–159.