Margot and Anne went into hiding with their parents Otto and Edith. They were later joined by Hermann van Pels, Otto's business partner, including his wife Auguste and their teenage son Peter. Their hiding place was in the sealed-off upper rooms of the annex at the back of Otto's company building in Amsterdam. Otto Frank started his business, named Opekta, in 1933. He was licensed to manufacture and sell pectin, a substance used to make jam. He stopped running his business while in hiding. But once he returned in the summer of 1945, he found his employees running it. The rooms that everyone hid in were concealed behind a movable bookcase in the same building as Opekta. The dentist of helper Miep Gies, Fritz Pfeffer, joined them four months later. In the published version, names were changed: The van Pelses are known as the Van Daans, and Fritz Pfeffer as Albert Dussel. With the assistance of a group of Otto Frank's trusted colleagues, they remained hidden for two years and one month. On 4 August 1944, they were discovered and deported to Nazi concentration camps. They were long thought to have been betrayed, although there are indications that their discovery may have been accidental, that the police raid had actually targeted "ration fraud". Of the eight people, only Otto Frank survived the war. Anne was 15 years old when she died in Bergen-Belsen. The exact date of her death is unknown, and has long been believed to be in late February or early March, a few weeks before the prisoners were liberated by British troops on 15 April 1945. In the manuscript, her original diaries are written over three extant volumes. The first volume (the red-and-white checkered autograph book) covers the period between 14 June and 5 December 1942. Since the second surviving volume (a school exercise book) begins on 22 December 1943, and ends on 17 April 1944, it is assumed that the original volume or volumes between December 1942 and December 1943 were lostpresumably after the arrest, when the hiding place was emptied on Nazi instructions. However, this missing period is covered in the version Anne rewrote for preservation. The third existing volume (which was also a school exercise book) contains entries from 17 April to 1 August 1944, when Anne wrote for the last time three days before her arrest. The manuscript, written on loose sheets of