Rev 4:1 After this I looked, and, behold, a door [was] opened in heaven: and the first voice which I heard [was] as it were of a trumpet talking with me; which said, Come up hither, and I will shew thee things which must be hereafter. (references the Rapture, see also 1 Thessalonians 4.)
Rev 13:16 And he causeth all, both small and great, rich and poor, free and bond, to receive a mark in their right hand, or in their foreheads:
Rev 13:17 And that no man might buy or sell, save he that had the mark, or the name of the beast, or the number of his name
The Book of Daniel also supports the seven year Tribulation period.