Legal Deposit for Self-Published (And Other) Authors

Yesterday evening, I met up with an old friend (who is also an author) for dinner. Inevitably the conversation touched upon writing and I asked whether my friend had provided print copies of his novel to the British Library and the 5 other libraries as stipulated under Legal Deposit legislation. He was unaware of Legal Deposit as (I believe) are quite a few other authors. I therefore thought it would be helpful to furnish the below information pertaining to Legal Deposit.
In the below extract...