Farm organizations and other groups may find that portable bleachers can serve needs for many group meetings, whether indoors or out. If so, here is a basic plan and some tips on how to build some impressive bleachers.
Morford, V. J. and Eggenberger, Lewis
"Build Your Own Portable Bleachers,"
Iowa Farm Science: Vol. 16
, Article 5.
Available at: https://lib.dr.iastate.edu/farmscience/vol16/iss6/5