diff --git a/core-principles/design-maturity.md b/core-principles/design-maturity.md
index e8d1e98..d311ed2 100644
--- a/core-principles/design-maturity.md
+++ b/core-principles/design-maturity.md
@@ -4,3 +4,4 @@ Every API design MUST be resource-centric ([Web API Design Maturity Model Level
 An API design MAY be affordance-centric ([Web API Design Maturity Model Level 3](http://amundsen.com/talks/2016-11-apistrat-wadm/2016-11-apistrat-wadm.pdf)).
 
 
+(TODO: see API Design Process Appendix)
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