diff --git a/605.myco b/605.myco
deleted file mode 100644
index 843bc66..0000000
--- a/605.myco
+++ /dev/null
@@ -1,3 +0,0 @@
-= 605
-http://sakamoto.pl/weblog/17-building-a-luggable-for-no-reason/
-
diff --git a/672.myco b/672.myco
new file mode 100644
index 0000000..fb07f5b
--- /dev/null
+++ b/672.myco
@@ -0,0 +1,3 @@
+= 672
+http://www.mathreference.com/
+
diff --git a/Building a luggable computer (for absolutely no reason).myco b/Building a luggable computer (for absolutely no reason).myco
deleted file mode 100644
index b75af03..0000000
--- a/Building a luggable computer (for absolutely no reason).myco	
+++ /dev/null
@@ -1,3 +0,0 @@
-= Building a luggable computer (for absolutely no reason)
-http://sakamoto.pl/weblog/17-building-a-luggable-for-no-reason/
-
diff --git a/MathReference archive.myco b/MathReference archive.myco
new file mode 100644
index 0000000..8468fa7
--- /dev/null
+++ b/MathReference archive.myco	
@@ -0,0 +1,3 @@
+= MathReference archive
+http://www.mathreference.com/
+