U. Meyer, C. Dahle, N. Sneeuw, A. Jäggi, G. Beutler, and H. Bock. VIII Hotine-Marussi Symposium on Mathematical Geodesy, volume 142 of IAG Symposia, VIII Hotine-Marussi Symposium Rome, Italy, 17--21 June 2013, page 177--183. Springer, (2015)
Q. Chen, M. Weigelt, N. Sneeuw, and T. van Dam. VIII Hotine-Marussi Symposium on Mathematical Geodesy, volume 142 of IAG Symposia, VIII Hotine-Marussi Symposium Rome, Italy, 17--21 June 2013, page 75--80. Springer, (2015)