1. Accounting Principle Board Opinion No. 17 -Intangible Assets;AICPA 1970b
2. Is older goodwill value relevant?;M & Bugeja;Accounting and Finance,2006
3. Equity valuation and negative earnings: the role of book value of equity;D W Collins;The Accounting Review,1999
4. Statement of Financial Accounting Standard No. 141 -Business combinations, Financial Accounting Standard Board, USA. FASB 2001b, Statement of Financial Accounting Standard No. 142 -Goodwill and other intangible assets;FASB 2001a