diff --git a/doc/classdiagram.xml b/doc/classdiagram.xml
new file mode 100644
index 0000000..5ac3bc8
--- /dev/null
+++ b/doc/classdiagram.xml
@@ -0,0 +1 @@
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\ No newline at end of file
diff --git a/doc/usecase.xml b/doc/usecase.xml
index b901a20..5307609 100644
--- a/doc/usecase.xml
+++ b/doc/usecase.xml
@@ -1 +1 @@
-<mxfile host="www.draw.io" modified="2019-12-12T09:57:02.619Z" agent="Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_1) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.0.3 Safari/605.1.15" etag="TAtIMbDBpFkcvHMbsqmK" version="12.3.9" type="device" pages="1"><diagram id="jCZ_pu6ezyKGmVCC1v1x" name="Page-1">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</diagram></mxfile>
\ No newline at end of file
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