Abnormal Strain Changes Prior to the M7.0 Lushan Earthquake Observed 
by a Borehole Strainmeter at Guzan
QIU Zehua,YANG Guang,TANG Lei,GUO Yanping,ZHANG Baohong
jgg . 2015, (1): 158 -161 .  DOI: 10.14075/j.jgg.2015.01.036