Power to requisition books and assets enables transfer of custody for relevant wealth tax proceedings. Section 37B empowers tax authorities to requisition books, documents or assets held by other authorities when such items are relevant to Wealth-tax proceedings or when assets disproportionate to known assets have been taken into custody elsewhere; authorised officers may require the custodian authority to deliver those items either immediately or when retention is no longer necessary, and items so delivered are to be treated, as far as practicable, as seized under Section 37A with the procedural provisions of sub-sections (5)-(12) of Section 37A and Section 37C applying to the requisitioning officer.