"Day of week" of the given date as an integer. Monday as the first day of the week is assigned a "1", Wednesday a "3", Saturday a "6", and Sunday a "7" and so on.
<dayofweek> is an optional element and must be given as the last one inside <date>.
It makes no sense to give <dayofweek> without specifying the date exactly. If <dayofweek> is set, it is compulsory to give <year>, <month>, and <day> before, too.
<date>
see <date>