@article {zumberge2002measurement, title = {Measurement of vertical strain and velocity at Siple Dome, Antarctica, with optical sensors}, journal = {Journal of Glaciology}, volume = {48}, number = {161}, year = {2002}, pages = {217{\textendash}225}, publisher = {International Glaciological Society}, author = {Zumberge, Mark A and Elsberg, Daniel H and Harrison, William D and Husmann, Eric and Morack, John L and Erin C Pettit and Waddington, Edwin D} }