diff --git a/src/documentation/content/xdocs/changes.xml b/src/documentation/content/xdocs/changes.xml
index 14dcd3b4f..cd8684240 100644
--- a/src/documentation/content/xdocs/changes.xml
+++ b/src/documentation/content/xdocs/changes.xml
@@ -65,6 +65,8 @@
This is very simple. All the text for the document is + stored in a single bit of the Quill CONTENTS. The text + is stored as little endian 16 bit unicode strings.
+The first four bytes seem to hold the count of the + entries in the bit, and the second four bytes seem to hold + the type. There is then some pre-data, and then data for + each of the entries, the exact format dependant on the type.
+Type 0 has 4 2 byte unsigned ints, then a pair of 2 byte + unsigned ints for each entry.
+Type 4 has 4 2 byte unsigned ints, then a pair of 4 byte + unsigned ints for each entry.
+Type 8 has 7 2 byte unsigned ints, then a pair of 4 byte + unsigned ints for each entry.
+Type 12 holds hyperlinks, and is very much more complex.
+ See org.apache.poi.hpbf.model.qcbits.QCPLCBit
+ for our best guess as to how the contents match up.