Routledge is an imprint of the Taylor & Francis Group, an informa business © 2020 selection and editorial matter, Michael J. Butler; individual chapters, the contributors The right of Michael J. Butler to be identified as the author of the editorial matter, and of the authors for their individual chapters, has been asserted in accordance with sections 77 and 78 of the Copyright, Designs and Patents Act 1988.With the exception of Chapter 6, no part of this book may be reprinted or reproduced or utilised in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers.Chapter 6 of this book is available for free in PDF format as Open Access from the individual product page at www.routledge.com. It has been made available under a Creative Commons Attribution-Non Commercial-No Derivatives 4.0 license.