4 ms·
Halliburton at one point attempted to patent it. http://www.google.com/patents/US20080270152 http://www.google.com/patents/US20080270152
by jml7c5 11y ago
Halliburton at one point attempted to patent it. http://www.google.com/patents/US20080270152 http://www.google.com/patents/US20080270152