diff --git a/disks/dec/rk03/README.md b/disks/dec/rk03/README.md
index 77f74efb00..86b8466f50 100644
--- a/disks/dec/rk03/README.md
+++ b/disks/dec/rk03/README.md
@@ -11,7 +11,7 @@ RK03 disks are single-platter cartridges with 203 tracks per side, 12 sectors pe
 256 words (512 bytes), for a total capacity of 2.38Mb (2,494,464 bytes).  They are used with an
 [RK11 Disk Controller](/devices/pdp11/rk11/).
 
-* [RT-11 v4.0](rtl11v4/) [[source](http://skn.noip.me/pdp11/rk1.dsk)]
+* [RT-11 v4.0](rt11v4/) [[source](http://skn.noip.me/pdp11/rk1.dsk)]
 * [XXDP+ Diagnostics](xxdp/) [[source](http://skn.noip.me/pdp11/rk2.dsk)]
 
 ---