(1) In this section -
'taxpayer' means a person whose identity is not known to the authorised officer, and a group or class of persons whose individual identities are not so known;
'third party' means a person whose identity has been furnished to an authorised officer by a financial institution in compliance with a notice issued under section 907 or an order made under section 908.
(2) An authorised officer may, subject to this section, make application to the Appeal Commissioners for consent, to serve a notice on a third party, requiring the third party -
(a) to make available for inspection by the authorised officer, such books, records or other documents as are in the third party's power, possession or procurement as contain, or may (in the authorised officer's reasonable opinion) contain information relevant to a liability in relation to a taxpayer, or
(b) to furnish to the authorised officer such information, explanations and particulars as the authorised officer may reasonably re
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