diff --git a/.lycheeignore b/.lycheeignore
index cd4ffb2f6..ff146a69d 100644
--- a/.lycheeignore
+++ b/.lycheeignore
@@ -12,4 +12,5 @@ https://m.dotdev.co/how-to-write-a-readme-that-rocks-bc29f279611a
 https://www.chathamhouse.org/about-us/chatham-house-rule
 https://www.linkedin.com/in
 # from source-code-inventory.md / no longer reachable but we want to keep the link in the pattern in case we find it again.
-https://github.com/trieshard/source-strategy-assessment/blob/master/framework.md
\ No newline at end of file
+https://github.com/trieshard/source-strategy-assessment/blob/master/framework.md
+https://dl.acm.org/doi/10.5555/3158161.3158175
\ No newline at end of file
diff --git a/meta/pattern-system.md b/meta/pattern-system.md
index 4ab75bf7e..1f7be8ea5 100644
--- a/meta/pattern-system.md
+++ b/meta/pattern-system.md
@@ -78,7 +78,7 @@ our InnerSource pattern system.
 
 Takashi Iba has published an article in the ACM Digital Library from PLoP 2016:
 [A pattern language for creating pattern languages: 364 patterns for pattern
-mining, writing, and symbolizing](https://dl.acm.org/citation.cfm?id=3158175&CFID=831673585&CFTOKEN=74341142&qualifier=LU1011674)
+mining, writing, and symbolizing](https://dl.acm.org/doi/10.5555/3158161.3158175)
 
 - for those without ACM DL access, there is [an earlier draft of the paper from
 PLoP 2016](http://www.hillside.net/plop/2016/papers/three/26.3.pdf).