www.gov.uk/government/publications/penalties-for-enablers-of-tax-avoidance-schemes-technical-guidance
www.birketts.co.uk/insights/legal-updates/penalties-for-enablers-of-defeated-tax-avoidance-s
See also:
www.rpc.co.uk/perspectives/tax-take/tax-fraud-the-rise-of-the-professional-enabler/#page=1
viewpoints.shoosmiths.co.uk/post/102i030/will-the-enablers-of-aggressive-tax-avoidance-schemes-soon-be-prosecuted