diff --git a/assets/bibliography.bib b/assets/bibliography.bib
index 46d24fe..13a1cc6 100644
--- a/assets/bibliography.bib
+++ b/assets/bibliography.bib
@@ -317,9 +317,9 @@ @inproceedings{Hamrick2011
 	Author = {Hamrick, Jessica and Battaglia, Peter and Tenenbaum, Joshua B},
 	Booktitle = {Proceedings of the 33rd Annual Meeting of the Cognitive Science Society, Boston, MA},
 	Title = {Internal physics models guide probabilistic judgments about object dynamics},
-	Url = {http://web.mit.edu/pbatt/www/publications/HamrBattTene11CogSci33.pdf},
+	Url = {https://cogsci.mindmodeling.org/2011/papers/0350/paper0350.pdf},
 	Year = {2011},
-	Bdsk-Url-1 = {http://web.mit.edu/pbatt/www/publications/HamrBattTene11CogSci33.pdf}}
+	Bdsk-Url-1 = {https://cogsci.mindmodeling.org/2011/papers/0350/paper0350.pdf}}
 
 @inproceedings{Gerstenberg2012,
 	Author = {Gerstenberg, Tobias and Goodman, Noah D},
diff --git a/exercises/conditioning.md b/exercises/conditioning.md
index 0fc5503..4bd50be 100644
--- a/exercises/conditioning.md
+++ b/exercises/conditioning.md
@@ -67,7 +67,7 @@ viz.table(Infer({method:'enumerate'}, model));
 
 ## Exercise 2: Conditioning and Intervention
 
-In the earlier [Medical Diagnosis]({{site.baseurl}}/chapters/02-generative-models.html#example-causal-models-in-medical-diagnosis) section we suggested understanding the patterns of symptoms for a particular disease by changing the prior probability of the disease such that it is always true (also called the *do* operator).
+In the earlier [Medical Diagnosis]({{site.baseurl}}/chapters/generative-models.html#example-causal-models-in-medical-diagnosis) section we suggested understanding the patterns of symptoms for a particular disease by changing the prior probability of the disease such that it is always true (also called the *do* operator).
 
 ~~~~
 var lungCancer = flip(0.01);