Clean up docstring

selector/measures/diversity.py

@@ -137,14 +137,16 @@ def logdet(x: np.ndarray) -> float:
 
     Notes
     -----
-    The log-determinant function is based on the formula in [1]_. Please note that we used the
+    The log-determinant function is based on the formula in Nakamura, T., Sci Rep 2022.
+    Please note that we used the
     natural logrithim to avoid the numerical stability issues,
     https://github.com/theochem/Selector/issues/229.
 
-    .. [1] Nakamura, T., Sakaue, S., Fujii, K., Harabuchi, Y., Maeda, S., and Iwata, S..,
-       Selecting molecules with diverse structures and properties by maximizing
-       submodular functions of descriptors learned with graph neural networks.
-       Scientific Reports 12, 2022.
+    References
+    ----------
+    Nakamura, T., Sakaue, S., Fujii, K., Harabuchi, Y., Maeda, S., and Iwata, S.., Selecting
+    molecules with diverse structures and properties by maximizing submodular functions of
+    descriptors learned with graph neural networks. Scientific Reports 12, 2022.
 
     """
     mid = np.dot(x, np.transpose(x)) + np.identity(x.shape[0])