diff --git a/doc/lbmref.md b/doc/lbmref.md
index 3ed66302..c2dcc805 100644
--- a/doc/lbmref.md
+++ b/doc/lbmref.md
@@ -157,6 +157,12 @@ expression evaluates to `t`.
 (eq '(1 (1 2)) '(1 (1 2)))
 ```
 
+---
+
+### not-eq
+
+`not-eq` implements the negation of eq. In other words, `(not-eq a b c)` evaluates
+to the same result as `(not (eq a b c))`. 
 
 ---
 
@@ -179,6 +185,13 @@ Example of `=` comparison.
 ```
 
 
+---
+
+### !=
+
+The `!=` operation implements the negation of `=`. So, `(!= a b)` evaluates
+to the same result as `(not (= a b))`.
+
 ---
 
 ### >
diff --git a/include/lbm_version.h b/include/lbm_version.h
index ef3e02e6..d885a8bf 100644
--- a/include/lbm_version.h
+++ b/include/lbm_version.h
@@ -33,6 +33,13 @@ extern "C" {
 
 /*! \page changelog Changelog
 
+Nov 9: Version 0.7.1
+  - not-eq and != added.
+  - Corrected behaviour for eval when applied to no argument.
+  - lbm_memory operations are protected by mutex.
+  - Fixes to eval-program.
+  - Added multiple condition conditional function called cond.
+
 Oct 31: Version 0.7.1
   - Added optional boolean guards to pattern matches.
   - Built in map and reverse.
diff --git a/src/tokpar.c b/src/tokpar.c
index 4898c8b2..4b862a77 100644
--- a/src/tokpar.c
+++ b/src/tokpar.c
@@ -229,7 +229,7 @@ static char translate_escape_char(char c) {
   }
 }
 
-int tok_string(lbm_char_channel_t *chan) {
+int tok_string(lbm_char_channel_t *chan, unsigned int *string_len) {
 
   unsigned int n = 0;
   unsigned int len = 0;
@@ -264,6 +264,7 @@ int tok_string(lbm_char_channel_t *chan) {
   if (r == CHANNEL_MORE) return TOKENIZER_NEED_MORE;
   if (c != '\"') return TOKENIZER_STRING_ERROR;
 
+  *string_len = len;
   n ++;
   return (int)n;
 }
@@ -604,16 +605,17 @@ lbm_value lbm_get_next_token(lbm_char_channel_t *chan, bool peek) {
     return lbm_enc_sym(SYM_TOKENIZER_WAIT);
   }
 
-  n = tok_string(chan);
+  unsigned int string_len = 0;
+  n = tok_string(chan, &string_len);
   if (n >= 2) {
     if (!peek) lbm_channel_drop(chan, (unsigned int)n);
     // TODO: Proper error checking here!
     // TODO: Check if anything has to be allocated for the empty string
-    lbm_heap_allocate_array(&res, (unsigned int)(n-2)+1, LBM_TYPE_CHAR);
+    lbm_heap_allocate_array(&res, (unsigned int)(string_len+1), LBM_TYPE_CHAR);
     lbm_array_header_t *arr = (lbm_array_header_t*)lbm_car(res);
     char *data = (char *)arr->data;
-    memset(data, 0, (unsigned int)((n-2)+1) * sizeof(char));
-    memcpy(data, sym_str, (unsigned int)(n - 2) * sizeof(char));
+    memset(data, 0, (string_len+1) * sizeof(char));
+    memcpy(data, sym_str, string_len * sizeof(char));
     return res;
   } else if (n == TOKENIZER_NEED_MORE) {
     return lbm_enc_sym(SYM_TOKENIZER_WAIT);
diff --git a/tests/test_eq_not_eq_1.lisp b/tests/test_eq_not_eq_1.lisp
new file mode 100644
index 00000000..fc58ed73
--- /dev/null
+++ b/tests/test_eq_not_eq_1.lisp
@@ -0,0 +1,13 @@
+
+(define a 10)
+(define b 20)
+(define c 30)
+
+(and (eq (not (eq a b c)) (not-eq a b c))
+     (eq (not (eq a a c)) (not-eq a a c))
+     (eq (not (eq a a a)) (not-eq a a a))
+     (eq (not (eq b b c)) (not-eq b b c))
+     (eq (not (eq b b b)) (not-eq b b b))
+     (eq (not (eq c b c)) (not-eq c b c))
+     (eq (not (eq c c c)) (not-eq c c c)))
+     
diff --git a/tests/test_eq_not_eq_2.lisp b/tests/test_eq_not_eq_2.lisp
new file mode 100644
index 00000000..82ece687
--- /dev/null
+++ b/tests/test_eq_not_eq_2.lisp
@@ -0,0 +1,11 @@
+(define a 10)
+(define b 20)
+(define c 30)
+
+(and (eq (not (= a b c)) (!= a b c))
+     (eq (not (= a a c)) (!= a a c))
+     (eq (not (= a a a)) (!= a a a))
+     (eq (not (= b b c)) (!= b b c))
+     (eq (not (= b b b)) (!= b b b))
+     (eq (not (= c b c)) (!= c b c))
+     (eq (not (= c c c)) (!= c c c)))
diff --git a/tests/test_string_1.lisp b/tests/test_string_1.lisp
new file mode 100644
index 00000000..6e22dae8
--- /dev/null
+++ b/tests/test_string_1.lisp
@@ -0,0 +1,4 @@
+
+(and (= (array-size "apa") 4)
+     (= (array-size "bepa") 5)
+     (= (array-size "kurt1") 6))