  Logic $L$ was introduced by Lewitzka [7] as a modal system that combines
intuitionistic and classical logic: $L$ is a conservative extension of CPC and
it contains a copy of IPC via the embedding $\varphi\mapsto\square\varphi$. In
this article, we consider $L3$, i.e. $L$ augmented with S3 modal axioms, define
basic epistemic extensions and prove completeness w.r.t. algebraic semantics.
The resulting logics combine classical knowledge and belief with intuitionistic
truth. Some epistemic laws of Intuitionistic Epistemic Logic studied by Artemov
and Protopopescu [1] are reflected by classical modal principles. In
particular, the implications "intuitionistic truth $\Rightarrow$ knowledge
$\Rightarrow$ classical truth" are represented by the theorems
$\square\varphi\rightarrow K\varphi$ and $K\varphi\rightarrow\varphi$ of our
logic $EL3$, where we are dealing with classical instead of intuitionistic
knowledge. Finally, we show that a modification of our semantics yields
algebraic models for the systems of Intuitionistic Epistemic Logic introduced
in [1].
