From eb64fb3514b954964387045bfaa03b64e1eb1793 Mon Sep 17 00:00:00 2001
From: Torsten Sommer <torsten.sommer@3ds.com>
Date: Wed, 26 Jun 2019 21:25:51 +0200
Subject: [PATCH] Add RFC 2119 key words to preamble (#584)

---
 docs/0___preamble.adoc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/docs/0___preamble.adoc b/docs/0___preamble.adoc
index 211bcb114..8e31778c5 100644
--- a/docs/0___preamble.adoc
+++ b/docs/0___preamble.adoc
@@ -187,3 +187,5 @@ used to define the sparseness structure of partial derivative matrices).
 In order to access an array element the C convention is used.
 For example,
 the first element of input argument `x` for function `setContinuousStates` is `x[0]`.
+
+* The key words *MUST*, *MUST NOT*, *REQUIRED*, *SHALL*, *SHALL NOT*, *SHOULD*, *SHOULD NOT*, *RECOMMENDED*, *NOT RECOMMENDED*, *MAY*, and *OPTIONAL* in this document are to be interpreted as described in https://tools.ietf.org/html/rfc2119[RFC 2119].