diff --git a/sample-book.pdf b/sample-book.pdf
index b72a784..07b28ed 100644
Binary files a/sample-book.pdf and b/sample-book.pdf differ
diff --git a/sample-handout.pdf b/sample-handout.pdf
index 803d7c7..08d5f88 100644
Binary files a/sample-handout.pdf and b/sample-handout.pdf differ
diff --git a/tufte-common.sty b/tufte-common.sty
index 9ff7a02..26bdc92 100644
--- a/tufte-common.sty
+++ b/tufte-common.sty
@@ -509,7 +509,7 @@
 %%
 % Citations should go in the margin as sidenotes
 
-\RequirePackage{natbib}
+\RequirePackage[numbers]{natbib}
 \RequirePackage{bibentry}	% allows bibitems to be typeset outside thebibliography environment
 % Redefine the \BR@b@bibitem command to fix a bug with bibentry+chicago style
 \renewcommand\BR@b@bibitem[2][]{%