Alfredo Ferro Rosalba Giugno Alfredo Pulvirenti Efficient Boundary Values Generation in General Metric Spaces for Software Component Testing. 318-331 http://dx.doi.org/10.1007/978-3-540-39910-0_15 2003 conf/birthday/2003manna Verification: Theory and Practice db/conf/birthday/Manna2003.html#FerroGP03