diff --git a/src/gmio_core/internal/ascii_parse.h b/src/gmio_core/internal/ascii_parse.h
index 730bcf3..fbcb257 100644
--- a/src/gmio_core/internal/ascii_parse.h
+++ b/src/gmio_core/internal/ascii_parse.h
@@ -29,6 +29,12 @@ void  gmio_ascii_stream_fwd_iterator_init(gmio_ascii_stream_fwd_iterator_t* it);
 char* gmio_current_char(const gmio_ascii_stream_fwd_iterator_t* it);
 void  gmio_skip_spaces(gmio_ascii_stream_fwd_iterator_t* it);
 int   gmio_eat_word(gmio_ascii_stream_fwd_iterator_t* it, gmio_ascii_string_buffer_t* buffer);
+
+/*! \brief Converts the string pointed to by \p str to gmio_real32_t representation
+ *
+ *  \retval 0  On success
+ *  \retval -1 On error(check \c errno to see what happened)
+ */
 int   gmio_get_real32(const char* str, gmio_real32_t* value_ptr);
 
 char*       gmio_next_char(gmio_ascii_stream_fwd_iterator_t* it);
diff --git a/src/gmio_stl/stl_format.h b/src/gmio_stl/stl_format.h
index fb7ffac..4c8a61e 100644
--- a/src/gmio_stl/stl_format.h
+++ b/src/gmio_stl/stl_format.h
@@ -19,11 +19,12 @@ typedef enum gmio_stl_format gmio_stl_format_t;
 
 /*! \brief Returns the format of the STL data in \p stream
  *
- *  It will try to read 512 bytes from \p stream into a buffer and then analyses this data to guess
- *  the format.
+ *  It will try to read 512 bytes from \p stream into a buffer and then
+ *  analyses this data to guess the format.
  *
- *  Parameter \p data_size must provide the total size (in bytes) of the stream data (e.g. file
- *  size), it is required to guess endianness in case of binary format.
+ *  Parameter \p data_size must provide the total size (in bytes) of the
+ *  stream data (e.g. file size), it is required to guess endianness in case
+ *  of binary format.
  *
  *  Returns GMIO_STL_UNKNOWN_FORMAT in case of error.
  */
diff --git a/src/gmio_stl/stl_io.h b/src/gmio_stl/stl_io.h
index 1c64fe5..c7d7621 100644
--- a/src/gmio_stl/stl_io.h
+++ b/src/gmio_stl/stl_io.h
@@ -20,7 +20,7 @@ GMIO_C_LINKAGE_BEGIN
  */
 struct gmio_stla_read_options
 {
-  void* dummy; /*!< Structs must have at least one member ... */
+  void* dummy; /*!< Structs must have at least one member in strict ISO-C90 */
   /* Flag to force locale ? */
 };
 typedef struct gmio_stla_read_options  gmio_stla_read_options_t;
@@ -29,9 +29,10 @@ typedef struct gmio_stla_read_options  gmio_stla_read_options_t;
  *
  *  \p options should be always set to NULL (not used for the moment)
  */
-GMIO_LIBSTL_EXPORT int gmio_stla_read(gmio_stl_mesh_creator_t* creator,
-                                      gmio_transfer_t* trsf,
-                                      const gmio_stla_read_options_t* options); /* NULL */
+GMIO_LIBSTL_EXPORT
+int gmio_stla_read(gmio_stl_mesh_creator_t* creator,
+                   gmio_transfer_t* trsf,
+                   const gmio_stla_read_options_t* options); /* NULL */
 
 /*! \brief Options for gmio_stla_write()
  */
@@ -55,9 +56,10 @@ typedef struct gmio_stla_write_options  gmio_stla_write_options_t;
  *  \return Error code
  *  \retval GMIO_NO_ERROR If operation successful
  */
-GMIO_LIBSTL_EXPORT int gmio_stla_write(const gmio_stl_mesh_t* mesh,
-                                       gmio_transfer_t* trsf,
-                                       const gmio_stla_write_options_t* options);
+GMIO_LIBSTL_EXPORT
+int gmio_stla_write(const gmio_stl_mesh_t* mesh,
+                    gmio_transfer_t* trsf,
+                    const gmio_stla_write_options_t* options);
 
 /* ============================================================================
  *  STL binary
@@ -75,9 +77,10 @@ typedef struct gmio_stlb_read_options  gmio_stlb_read_options_t;
 
 /*! \brief Read geometry from STL binary stream
  */
-GMIO_LIBSTL_EXPORT int gmio_stlb_read(gmio_stl_mesh_creator_t* creator,
-                                      gmio_transfer_t* trsf,
-                                      const gmio_stlb_read_options_t* options);
+GMIO_LIBSTL_EXPORT
+int gmio_stlb_read(gmio_stl_mesh_creator_t* creator,
+                   gmio_transfer_t* trsf,
+                   const gmio_stlb_read_options_t* options);
 
 
 /*! \brief Options for gmio_stlb_write()
@@ -94,9 +97,10 @@ typedef struct gmio_stlb_write_options  gmio_stlb_write_options_t;
 
 /*! \brief Write geometry in the STL binary format
  */
-GMIO_LIBSTL_EXPORT int gmio_stlb_write(const gmio_stl_mesh_t* mesh,
-                                       gmio_transfer_t* trsf,
-                                       const gmio_stlb_write_options_t* options);
+GMIO_LIBSTL_EXPORT
+int gmio_stlb_write(const gmio_stl_mesh_t* mesh,
+                    gmio_transfer_t* trsf,
+                    const gmio_stlb_write_options_t* options);
 
 GMIO_C_LINKAGE_END