Retrieved 16 June 2018. ↑ Guillén 2015, p. 3 1 2 Guillén 2015, p. 14 ↑ Guillén 2015, p. 21 ↑ Guillén 2015, p. 31 ↑ Guillén 2015, p. 49 ↑ Guillén 2015, p. 67 1 2 "Diego Costa: Jose Mourinho hails 'special' Chelsea striker".