diff --git a/HACKING b/HACKING
index ec7cacf85..9dae74a74 100644
--- a/HACKING
+++ b/HACKING
@@ -609,7 +609,7 @@ SPOT macros
     that a compiler might not see as unreachable.
 
   * Use SPOT_API in front of functions and class that should be
-    exported by the shared library.  See "Exporting symbolss" above.
+    exported by the shared library.  See "Exporting symbols" above.
 
   * Use SPOT_ASSERT(...) if you ever have to put an assertion in
     some header file.  See "Assertions" above.
diff --git a/doc/tl/tl.tex b/doc/tl/tl.tex
index 1831e66ab..dbaad34ce 100644
--- a/doc/tl/tl.tex
+++ b/doc/tl/tl.tex
@@ -206,7 +206,7 @@
 
 Let $\N=\{0,1,2,\ldots\}$ denote the set of natural numbers and
 $\omega\not\in\N$ the first transfinite ordinal.  We extend the $<$
-relation from $\N$ to $\N\cup\{\omega\}$ with $\forall n\in N,\,
+relation from $\N$ to $\N\cup\{\omega\}$ with $\forall n\in \N,\,
 n<\omega$.  Similarly let us extend the addition and subtraction with
 $\forall n\in\N,\,\omega+n = \omega-n = \omega+\omega = \omega$.
 
@@ -1323,8 +1323,8 @@ rewriting arrange any PSL formula into negative normal form.
   \NOT(f \M g) & \equiv (\NOT f) \W (\NOT g)&
   \NOT(\sere{r} \Esuffix f) &\equiv \sere{r} \Asuffix \NOT f
 \end{align*}
-\noindent Recall the that negated weak closure $\nsere{r}$ is actually
-implemented as a specific operator, so it not actually prefixed by the
+\noindent Recall that the negated weak closure $\nsere{r}$ is actually
+implemented as a specific operator, so it is not actually prefixed by the
 $\NOT$ operator.
 \begin{align*}
   f \XOR g & \equiv ((\NOT f)\AND g)\OR(f\AND\NOT g) &
diff --git a/spot/tl/formula.hh b/spot/tl/formula.hh
index 4b299ba58..28c04216e 100644
--- a/spot/tl/formula.hh
+++ b/spot/tl/formula.hh
@@ -72,7 +72,7 @@ namespace spot
     G,                         ///< Globally
     Closure,                   ///< PSL Closure
     NegClosure,                ///< Negated PSL Closure
-    NegClosureMarked,          ///< marked version of the Negated PSL Clusure
+    NegClosureMarked,          ///< marked version of the Negated PSL Closure
     // binary operators
     Xor,                       ///< Exclusive Or
     Implies,                   ///< Implication