| 摘要 |
<p>The method consists of nullifying on a ticket (1) a predetermined number of squares in a first series of squares (5) by the removal of an opaque layer (11) coated thereon and carrying the data to be validated by uncovering, under each square, a respective symbol (10), and of nullifying all the squares in a second series of squares (6) by the removal of an opaque layer (11) coated thereon and carrying said symbols (10), excepting for those squares which carry identical symbols (10) of those uncovered in the first series of squares (5). If the squares uncovered from the first series (5) identify a date, the presence on a ticket (1) of covered squares in the second series (6) carrying the same symbols (10) as appear in the uncovered squares from the first series (5) certifies that the squares in the second series (6) have been uncovered after uncovering the squares in the first series (5), thus validating the identified date.</p> |
