21.The commentary uses a number of abbreviations. They are listed below.
| APA | advance pricing agreement |
| CAA | the Capital Allowances Act 2001 |
| CRCA | the Commissioners for Revenue and Customs Act 2005 |
| CTA 2009 | the Corporation Tax Act 2009 |
| CTA 2010 | the Corporation Tax Act 2010 |
| DTA | double taxation arrangement |
| DTR | double taxation relief |
| FA 1964 | Finance Act 1964 (and similarly for other Finance Acts) |
| F(No 2)A | Finance (No 2) Act |
| GAAP | generally accepted accounting practice |
| HMRC | Her Majesty’s Revenue and Customs |
| ICTA | the Income and Corporation Taxes Act 1988 |
| ITA | the Income Tax Act 2007 |
| ITEPA | the Income Tax (Earnings and Pensions) Act 2003 |
| ITTOIA | the Income Tax (Trading and Other Income) Act 2005 |
| OTA 1975 | the Oil Taxation Act 1975 |
| PRT | petroleum revenue tax |
| TCGA | the Taxation of Chargeable Gains Act 1992 |
| TMA | the Taxes Management Act 1970 |