1988, PC Mag (volume 7, number 17, 11 October 1988, page 93)You'll find a mix among clamshell laptops for strong laps, lunchboxes, and sewing-machine configurations; the latter two designs typically have detachable keyboards.
2004, Scott Mueller, Upgrading and Repairing Laptops (page 20)The performance difference between desktops and lunchboxes was practically nil.