update docs

docs/about/tools.md

@@ -14,7 +14,22 @@ Zhang Y\*, Zhang XO\*, Chen T, Xiang JF, Yin QF, Xing YH, Zhu S, Yang L# and Che
 
 Dong R, Zhang XO, Zhang Y, Ma XK, Chen LL and Yang L. CircRNA-derived pseudogenes. *Cell Res*, 2016, 15:611-624. [[Paper](http://www.ncbi.nlm.nih.gov/pubmed/27021280)] [[Github](https://github.com/YangLab/CIRCpseudo)]
 
+### CSI
+
+Dong R\*, Ma XK\*, Chen LL# and Yang L#. Increased complexity of circRNA expression during species evolution. *RNA Biol*, 2017, 14:1064-1074
+[[Paper](https://www.tandfonline.com/doi/full/10.1080/15476286.2016.1269999)] [[Github](https://github.com/YangLab/CSI)]
+
+### CLEAR
+
+Ma XK\*, Wang MR, Liu CX, Dong R, Carmichael GG, Chen LL and Yang L#. A CLEAR pipeline for direct comparison of circular and linear RNA expression. 2019, *bioRxiv*. doi: 10.1101/668657
+[[Paper](https://www.biorxiv.org/content/10.1101/668657v2)] [[Github](https://github.com/YangLab/CLEAR)]
+
 ### CIRCpedia
 
+[[Website](http://www.picb.ac.cn/rnomics/circpedia/)]
+
 Zhang XO\*, Dong R\*, Zhang Y\*, Zhang JL, Luo Z, Zhang J, Chen LL#, Yang L#. Diverse alternative back-splicing and alternative splicing landscape of circular RNAs. *Genome Res*, 2016, 26:1277-1287
-[[Paper](http://genome.cshlp.org/content/26/9/1277.abstract)] [[Website](http://www.picb.ac.cn/rnomics/circpedia/)]
+[[Paper](http://genome.cshlp.org/content/26/9/1277.abstract)]
+
+Dong R\*, Ma XK\*, Li GW, Yang L#. CIRCpedia v2: An Updated Database for Comprehensive CircRNA Annotation and Expression Comparison. *Genomics Proteomics Bioinformatics*, 2018, doi:10.1016/j.gpb.2018.08.001
+[[Paper](https://www.sciencedirect.com/science/article/pii/S1672022918302596)]