Update README.md

README.md

@@ -16,6 +16,6 @@ Precursor sequence    Precursor charge      Quant
   NPAADAGSNNASKK              2           32,234,856
       IVLVDDSIVR              2           11,768,772
 ```
-Specter currently requires the cluster-computing framework Apache Spark; a cloud framework and accompanying website will appear in the future. See ```SpecterUserGuide.pdf``` for detailed instructions on how to set up and use Specter.
+Specter currently requires the cluster-computing framework Apache Spark; a cloud framework and accompanying website will appear in the future. See ```SpecterUserGuide.pdf``` for detailed instructions on how to set up and use Specter. To learn more about the algorithm, you can read about Specter in *Nature Methods*: dx.doi.org/10.1038/nmeth.4643.