Update README.md

Z80coder · web-flow · commit 78b5a357907d · 2023-05-15T09:48:03.000+01:00
diff --git a/README.md b/README.md
@@ -10,7 +10,7 @@ Questions? Ask @Z80coder
 
 ## Draft paper
 
-["∂B nets: learning discrete functions by gradient descent"](./docs/db.pdf) (April 2023).
+["∂B nets: learning discrete functions by gradient descent"](https://arxiv.org/abs/2305.07315) (April 2023).
 
 ## Demos
 
