Alternative successions of the English and British crown of the "Clarence" claim also draw on the debated validity of Edward IV's marriage to Elizabeth Woodville, which allows them to argue that, even if Edward was legitimate, his children were not. Another point is that Henry VI passed a law in 1470 that should both he and his son Edward of Westminster die without further legitimate issue, the crown was to pass to "Clarence", as Henry had placed an attainder upon Edward IV. When Henry died in 1471 (Prince Edward having died in battle shortly before), "Clarence" (who could claim descent from John of Gaunt, as could his wife
IEEE 1471 of software-intensive systems". It has long been recognized that "architecture" has a strong influence over the life cycle of a system. However, until relatively recently, hardware issues have tended to dominate architectural thinking, and software aspects, when considered at all, were often the first to be compromised under the pressures of development. IEEE 1471 was created to provide a basis for thinking about the architecture of software-intensive systems. IEEE 1471's contributions can be summarised as follows (in this list, items in "italics" are terms defined by and used in the standard): IEEE 1471 provides informative annexes that relate its concepts