Update citationkeypatterns.md

Adds a note on generating institution keys. Uses the example given in JabRef/jabref#6942

en/setup/citationkeypatterns.md

@@ -36,6 +36,8 @@ Several special field markers are offered, which extract only a specific part of
 
 **Note:** If there is no author \(as in the case of an edited book\), then all of the above **`[auth...]`** markers will use the editor\(s\) \(if any\) as a fallback. Thus, the editor\(s\) of a book with no author will be treated as the author\(s\) for label-generation purposes. If you do not want this behavior, i.e. you require a marker which expands to nothing if there is no author, use **`pureauth`** instead of **`auth`** in the above codes. For example, **`[pureauth]`**, or **`[pureauthors3]`**.
 
+The name of institutions and companies often contain spaces and words that have a specific meaning in the author field, e.g., `and`. The full name should be enclosed in braces to prevent the name from being miss-parsed for these cases. Names enclosed in braces are often abbreviated while generating citation keys to avoid creating excessively long keys. For example, `{European Union Aviation Safety Agency}` is abbreviated to `EUASA`.
+
 #### Editor-related field markers
 
 * **`[edtr]`**: The last name of the first editor