The software is licensed through Engineering International Inc. rather than sold as individual files.
Daniel T. Li, Ph.D., S.E., is a prominent figure in the field of structural engineering, best known for developing an extensive library of professional structural design spreadsheets through his company, Engineering International Inc. . daniel t li spreadsheets
Licensed users can pay an annual upgrading fee to receive new software released throughout the year and stay current with code changes. About the Developer daniel t li spreadsheets