diff --git a/README.md b/README.md
index 9cd0e1f..5e0acbe 100644
--- a/README.md
+++ b/README.md
@@ -27,6 +27,7 @@ TODO
 - Better error messages during file I/O
 - Autocorrelation
 - Replica exchange
+- Unit tests for 2d/Nd WHAM
 
 License 
 ---
diff --git a/src/histogram.rs b/src/histogram.rs
index 395f4fb..cda7847 100644
--- a/src/histogram.rs
+++ b/src/histogram.rs
@@ -178,7 +178,7 @@ mod tests {
 			false // cyclic
 		)
 	}
-	
+
 	#[test]
 	fn calc_bias() {
 		let ds = build_hist_set(); // k = 10