minor formatting

README.md

@@ -59,15 +59,17 @@ This package contains a Python library to
 
 _Please cite the following if you use GOATOOLS in your research_:
 
-Klopfenstein DV, Zhang L, Pedersen BS ... Tang H [GOATOOLS: A Python library for Gene Ontology analyses](https://www.nature.com/articles/s41598-018-28948-z)    
+Klopfenstein DV, Zhang L, Pedersen BS, ... Tang H [GOATOOLS: A Python library for Gene Ontology analyses](https://www.nature.com/articles/s41598-018-28948-z)    
 _Scientific reports_ | (2018) 8:10872 | DOI:10.1038/s41598-018-28948-z
 
-To group GO terms, see examples in [find_enrichment examples](/doc/md/README_find_enrichment.md)
+**GO Grouping**: To group GO terms, see examples in
+[find_enrichment examples](/doc/md/README_find_enrichment.md)
 where the optional _--sections_ argument is used.    
 A detailed description of GOATOOLS GO grouping is found in the
 [manuscript](https://www.nature.com/articles/s41598-018-28948-z)
 
-The code for the stochastic GOEA simulations described in the paper is found here:    
+**Stochastic GOEA simulations**: The code for the stochastic GOEA simulations
+described in the paper is found here:    
 https://github.com/dvklopfenstein/goatools_simulation
 
 ## Installation