How much precision is needed to compare two sums of square roots of integers?

Jianbo Qian Cao An Wang How much precision is needed to compare two sums of square roots of integers? 194-198 2006 100 Inf. Process. Lett. 5 http://dx.doi.org/10.1016/j.ipl.2006.05.002 db/journals/ipl/ipl100.html#QianW06