4William D W,Harold D B,Allan R R. Ultra-light weight proppantdevelopment yields exciting new opportunities in hydraulicfracturing design [Z]. SPE 84309, 2003.
5Graham J W, Sinclair A R._High strength particulates [P].US4585064, 1986.
6Sinclair A R,Johnson R L._Composite and reinforced coatings onproppants and particles [P]. US 5597784,1997.
7Johnson C, Airobruster D. Particles covered with a cured infusiblethermoset film and process for their production [P]. US 4439489,1984.
8Sinclair A R, Johnson R L, Richard L. Composite and reinforcedcoating on proppants and particles [P].US 5422183,1995-06-06.