A woman signs the condolence book for Dutch Aids expert Joep Lange and his assistant Jacqueline van Tongeren, on July 19, 2014 in the Academic Medical Centre (AMC) in Amsterdam. Lange and Van Tongeren, were on their way to the International Aids Conference in Melbourne when their plane from Malaysia Airlines crashed in Ukraine, last Thusday. All passengers were killed. AFP PHOTO/ANP EVERT ELZINGA netherlands out (Photo credit should read EVERT ELZINGA/AFP/Getty Images)
