Add bibtex formatted citations per #229

Author: lmcinnes

README.rst

@@ -268,12 +268,34 @@ If you have used this codebase in a scientific publication and wish to cite it,
     In: Journal of Open Source Software, The Open Journal, volume 2, number 11.
     2017
 
+.. code:: bibtex
+    @article{mcinnes2017hdbscan,
+      title={hdbscan: Hierarchical density based clustering},
+      author={McInnes, Leland and Healy, John and Astels, Steve},
+      journal={The Journal of Open Source Software},
+      volume={2},
+      number={11},
+      pages={205},
+      year={2017}
+    }
+    
 To reference the high performance algorithm developed in this library please cite our paper in ICDMW 2017 proceedings.
 
     McInnes L, Healy J. *Accelerated Hierarchical Density Based Clustering* 
     In: 2017 IEEE International Conference on Data Mining Workshops (ICDMW), IEEE, pp 33-42.
     2017
 
+
+.. code:: bibtex
+    @inproceedings{mcinnes2017accelerated,
+      title={Accelerated Hierarchical Density Based Clustering},
+      author={McInnes, Leland and Healy, John},
+      booktitle={Data Mining Workshops (ICDMW), 2017 IEEE International Conference on},
+      pages={33--42},
+      year={2017},
+      organization={IEEE}
+    }
+
 ---------
 Licensing
 ---------