diff --git a/content/reference.gmi b/content/reference.gmi
index 86e0e38..f27ce91 100644
--- a/content/reference.gmi
+++ b/content/reference.gmi
@@ -9,5 +9,5 @@
 # interesting reads
 
 => gemini://drewdevault.com/2021/10/05/Terminal-emulation-legacy.gmi                        Terminal emulation legacy
-=> html://ploum.net/the-computer-built-to-last-50-years                                     The computer built to last 50 years [www]
+=> https://ploum.net/the-computer-built-to-last-50-years                                     The computer built to last 50 years [www]
 => https://jlouisramblings.blogspot.com/2012/08/getting-25-megalines-of-code-to-behave.html The softare of the Curiosity Mars rover [www]