diff --git a/.settings/edu.umd.cs.findbugs.core.prefs b/.settings/edu.umd.cs.findbugs.core.prefs
index dee7fa59a9ed17e644d3f7bc7c9ba7a13437de47..3c0de6d05abaa461f39153b10696cb45f2d7e01e 100644
--- a/.settings/edu.umd.cs.findbugs.core.prefs
+++ b/.settings/edu.umd.cs.findbugs.core.prefs
@@ -1,5 +1,5 @@
 #FindBugs User Preferences
-#Tue Mar 03 15:12:34 CET 2015
+#Wed Mar 18 10:50:24 CET 2015
 detector_threshold=3
 effort=max
 excludefilter0=.fbExcludeFilterFile|true
diff --git a/doc/concept/teetime-delay-problem.pdf b/doc/concept/teetime-delay-problem.pdf
new file mode 100644
index 0000000000000000000000000000000000000000..ab3ac10365b370324503c4c2ce91686c9e309f64
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index 0000000000000000000000000000000000000000..81c6cdb6e4379a9ad2a64fb9908039567a254dd7
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