Identification and characterization of cell type-specific and ubiquitous chromatin regulatory structures in the human genome. oleh Hualin Xi, Hennady P Shulha, Jane M Lin, Teresa R Vales, Yutao Fu, David M Bodine, Ronald D G McKay, Josh G Chenoweth, Paul J Tesar, Terrence S Furey, Bing Ren, Zhiping Weng, Gregory E Crawford