The term Quran code (also known as Code 19) refers to the claim that the Quranic text contains a hidden mathematically complex code. Advocates think that the code represents a mathematical proof of the divine authorship of the Quran. Proponents of the Quran code claim that the code is based on statistical procedures, however, this claim has not been validated by any independent mathematical or scientific institute. In 1969, Rashad Khalifa, an Egyptian-American biochemist, began analyzing the separated letters of the Quran (also called Quranic initials or Muqattaʿat), and the Quran to examine certain sequences of numbers. In 1973 he published the book Miracle of the Quran: Significance of the Mysterious Alphabets, in which he describes the Quranic initials through enumerations and distributions. In 1974, Khalifa claimed to have discovered a mathematical code hidden in the Quran, a code based around the number 19. He wrote the book The Computer Speaks: God's Message to the World, in which he thematizes this Quran code. He relies on Surah 74, verse 30 to prove the significance of the number: "Over it is nineteen,". Proponents of the code include United Submitters International (an association initiated by Rashad Khalifa) as well as some Quranists and traditional Muslims. Believers in Quran Code often use certain word counts, checksums and cross sums to legitimize the code. Edip Yüksel, a Turkish Quranistic author and colleague of Rashad Khalifa, makes the following claims in his book Nineteen: God's Signature in Nature and Scripture: The Basmala (bismi ʾllāhi ʾr-raḥmāni ʾr-raḥīmi), the Quranic opening formula, which, with one exception, is at the beginning of every Surah of the Quran, consists of exactly 19 letters. The first word of the Basmala, Ism (name), without contraction, occurs 19 times in the Quran (19×1). [Also no plural forms, or those with pronoun endings] The second word of the Basmala, Allah (God), occurs 2698 times (19×142). The third word of the Basmala, Rahman (Gracious), occurs 57 times (19×3).