Appendix A Sources of Information Pratt, Shannon P, Robert F. Reilly, and Robert P. Schweihs. 2000. Valuing ab bbusiness: The analysis and appraisal of closely held companies, 4th edition. Treasury Regulation 25.2512‐1 (Estate Planning) and Treasury Regulation b) (Estate Valuation. Trugman, Gary Rb Understanding business valuation ‐ a practical guide to valuing small to medium‐sized businesses, 2nd edition. Pratt, Shannon P, Robert F. Reilly, and Robert P. Schweihs. 1989. Valuing ab bbusiness: The analysis and appraisal of closely held companies, 2nd edition. Internal Revenue Service, Revenue Ruling 59‐60