Pengaruh manajemen modal kerja terhadap kinerja saham kinerja keuangan keputusan investasi dan risiko perusahaan pada perusahaan di sektor industri pertambangan yang terdaftar pada bursa efek Indonesia periode 2011-2013 = Analysis on the influence of working capital management on the performance of the stock financial performance investment decisions and risk companies in the mining industry company which listed on Indonesian stock exchange period 2011-2013