《旧唐书·列传·卷一百三十四》
凡击钟者，敲一下给百千钱；有顺从其心意的，敲到二十下，少的也有十下。
凡击钟者，一击百千；有规其意者，击至二十杵，少尚十杵。
Whoever struck the bell would be given a hundred thousand coins for each strike, and whoever struck it twenty times would be greatly favored, while the least would be ten times.