Optimisation of focused ultrasound extraction (FUSE) and microwave-assisted extraction (MAE) of hydrocarbons in geological chert samples - Olivares, Maitane; Vallejo Ruiz, Asier ‎; Irazola, Mireia; Murelaga, Xabier; Baceta, Juan Ignacio; Tarriño Vinagre, Antonio; Etxebarria Loizate, Nestor (2010)