William Laird Clowes,
The Royal Navy, a History from the Earliest Times to the Present…
(1890s)
“ To another publication of the Navy Records Society, Professor Laughton's, 'State Papers Relating to the Spanish Armada,' a great debt is due. Both it, and Captain Duro's works dealing with affairs of the same eventful time, have, as will be seen, been freely drawn upon. To Mr. Oppenheim personally, I owe several useful suggestions. It is a matter of great regret to me that both Professor Laughton and Mr. Oppenheim were obliged to decline invitations to contribute some chapters to this volume, and that one of the grounds of the latter's refusal was the uncertainty of his health. ”
