Citation Hunt

The Wikipedia snippet below is not backed by a reliable source. Can you find one?

Click I got this! to go to Wikipedia and fix the snippet, or Next! to see another one. Good luck!

In page Lace card:

This text is part of the article's lead section, so referencing it may be optional. Please see WP:CITELEAD for more information.

"

A lace card (also called a whoopee card, ventilator card, flyswatter card, or IBM doily[citation needed]) is a punched card with all holes punched.[1] They were mainly used as practical jokes to cause disruption in card readers. Card readers tended to jam when a lace card was inserted, as the resulting card had insufficient structural integrity to avoid buckling inside the mechanism. Card punchers could also jam trying to produce cards with all holes punched, owing to power-supply problems. When a lace card was fed through the reader, a card knife or card saw (a flat tool used with punched card readers and card punches) was needed to clear the jam.[2][3]