diff --git a/src/dtmc/atomic_proposition.h b/src/dtmc/atomic_proposition.h
index 3af284cc9..7b8e75690 100644
--- a/src/dtmc/atomic_proposition.h
+++ b/src/dtmc/atomic_proposition.h
@@ -54,9 +54,7 @@ class AtomicProposition {
 	      int n = (int) std::ceil(nodeCount / 64.0);
 	      node_array = new uint_fast64_t[n];
 	      //Initialization with 0 is crucial!
-	      for (int i = 0; i < n; i++) {
-	         node_array[i] = 0L;
-	      }
+	      memset(node_array, 0, n*sizeof(uint_fast64_t));
 	   }
 
 	}
diff --git a/src/dtmc/labelling.h b/src/dtmc/labeling.h
similarity index 82%
rename from src/dtmc/labelling.h
rename to src/dtmc/labeling.h
index ee3ce4199..f236bfaa4 100644
--- a/src/dtmc/labelling.h
+++ b/src/dtmc/labeling.h
@@ -5,19 +5,23 @@
  *      Author: Thomas Heinemann
  */
 
-#ifndef MRMC_DTMC_LABELLING_H_
-#define MRMC_DTMC_LABELLING_H_
+#ifndef MRMC_DTMC_LABELING_H_
+#define MRMC_DTMC_LABELING_H_
 
 #include "atomic_proposition.h"
 
-#define UNORDERED_MAP
 
-#ifdef UNORDERED_MAP
-#include "boost/unordered_map.hpp"
-#define MAP boost::unordered_map
-#else
+
+/* Map types: By default, the boost hash map is used.
+ * When the macro DEFAULT_MAP is defined, the default C++ class (std::map)
+ * is used instead.
+ */
+#ifdef DEFAULT_MAP
 #include <map>
 #define MAP std::map
+#else
+#include "boost/unordered_map.hpp"
+#define MAP boost::unordered_map
 #endif
 
 #include <stdexcept>
@@ -27,16 +31,16 @@ namespace mrmc {
 namespace dtmc {
 
 
-class labelling {
+class labeling {
    public:
 
 
-      labelling(const uint_fast32_t p_nodes) {
+      labeling(const uint_fast32_t p_nodes) {
          nodes = p_nodes;
       }
 
-      virtual ~labelling() {
-         //deleting all the labelling vectors in the map.
+      virtual ~labeling() {
+         //deleting all the labeling vectors in the map.
          MAP<std::string, AtomicProposition*>::iterator it;
          for (it = proposition_map.begin(); it != proposition_map.end(); ++it) {
             if (it->second != NULL) {
@@ -84,6 +88,7 @@ class labelling {
    private:
       uint_fast32_t nodes;
       MAP<std::string, AtomicProposition*> proposition_map;
+      //AtomicProposition** propositions;
       //boost::unordered_map<std::string, AtomicProposition*> proposition_map;
 };
 
@@ -91,4 +96,4 @@ class labelling {
 
 } //namespace mrmc
 
-#endif /* MRMC_DTMC_LABELLING_H_ */
+#endif /* MRMC_DTMC_LABELING_H_ */
diff --git a/src/mrmc-cpp.cpp b/src/mrmc-cpp.cpp
index 5b9bd59ef..666723a18 100644
--- a/src/mrmc-cpp.cpp
+++ b/src/mrmc-cpp.cpp
@@ -32,7 +32,7 @@ int main(int argc, char* argv[]) {
 	pantheios_be_file_setFilePath("log.all");
 	pantheios::log_INFORMATIONAL("MRMC-Cpp started.");
 
-	mrmc::dtmc::labelling *lab;
+	mrmc::dtmc::labeling *lab;
 
 	time_t start = std::clock();
 
diff --git a/src/parser/read_lab_file.cpp b/src/parser/read_lab_file.cpp
index 27da49622..3a8c7244d 100644
--- a/src/parser/read_lab_file.cpp
+++ b/src/parser/read_lab_file.cpp
@@ -9,8 +9,6 @@
 
 #include "read_lab_file.h"
 
-#include "src/dtmc/labelling.h"
-
 #include "src/exceptions/wrong_file_format.h"
 #include "src/exceptions/file_IO_exception.h"
 
@@ -30,7 +28,7 @@ namespace parser {
  * @param filename   input .lab file's name.
  * @return returns a pointer to a labelling object.
  */
-mrmc::dtmc::labelling * read_lab_file(int node_count, const char * filename)
+mrmc::dtmc::labeling * read_lab_file(int node_count, const char * filename)
 {
    /* Note that this function uses strtok_r on char-array s.
     * This function will modify this string.
@@ -57,7 +55,7 @@ mrmc::dtmc::labelling * read_lab_file(int node_count, const char * filename)
    }
 
 
-   mrmc::dtmc::labelling* result = new mrmc::dtmc::labelling(node_count);
+   mrmc::dtmc::labeling* result = new mrmc::dtmc::labeling(node_count);
 
    //Here, all propositions are to be declared...
    if (fgets(s, BUFFER_SIZE, P)) {
diff --git a/src/parser/read_lab_file.h b/src/parser/read_lab_file.h
index f4a2d0077..f51595af4 100644
--- a/src/parser/read_lab_file.h
+++ b/src/parser/read_lab_file.h
@@ -8,14 +8,14 @@
 #ifndef READ_LAB_FILE_H_
 #define READ_LAB_FILE_H_
 
-#include "src/dtmc/labelling.h"
+#include "src/dtmc/labeling.h"
 
 
 namespace mrmc {
 
 namespace parser {
 
-mrmc::dtmc::labelling * read_lab_file(int node_count, const char * filename);
+mrmc::dtmc::labeling * read_lab_file(int node_count, const char * filename);
 
 }
 }
diff --git a/test/parser/read_lab_file_test.cpp b/test/parser/read_lab_file_test.cpp
index 2702ddf3f..bee571f4a 100644
--- a/test/parser/read_lab_file_test.cpp
+++ b/test/parser/read_lab_file_test.cpp
@@ -6,7 +6,7 @@
  */
 
 #include "gtest/gtest.h"
-#include "src/dtmc/labelling.h"
+#include "src/dtmc/labeling.h"
 #include "src/parser/read_lab_file.h"
 #include "src/exceptions/file_IO_exception.h"
 #include "src/exceptions/wrong_file_format.h"
@@ -17,8 +17,8 @@ TEST(ReadLabFileTest, NonExistingFileTest) {
 }
 
 TEST(ReadLabFileTest, ParseTest) {
-   //This test is based on a testcase from the original MRMC.
-   mrmc::dtmc::labelling* labelling;
+   //This test is based on a test case from the original MRMC.
+   mrmc::dtmc::labeling* labelling;
 
    //Parsing the file
    ASSERT_NO_THROW(labelling = mrmc::parser::read_lab_file(12,"test/parser/lab_files/pctl_general_input_01.lab"));