  Recently, in order to mix algebraic and logic styles of specification in a
uniform framework, the notion of a logic labelled transition system (Logic LTS
or LLTS for short) has been introduced and explored. A variety of constructors
over LLTS, including usual process-algebraic operators, logic connectives
(conjunction and disjunction) and standard temporal operators (always and
unless), have been given. However, no attempt has made so far to develop
general theory concerning (nested) recursive operations over LLTSs and a few
fundamental problems are still open. This paper intends to study this issue in
pure process-algebraic style. A few fundamental properties, including
precongruence and the uniqueness of consistent solutions for equations, will be
established.
