[no title]

W. J. Langford

doi:10.2307/3614780

To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

[no title]

Your Kindle email address

@free.kindle.com @kindle.com (service fees apply)

Available formats PDF

By using this service, you agree that you will only keep content for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services

To save this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Dropbox account. Find out more about saving content to Dropbox.

[no title]

To save this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about saving content to Google Drive.

[no title]

Reply to: Submit a response

Title * Please enter a title for your response.

Contents * Please enter your response.

Your details

First name * Please enter your first name.

Last name * Please enter your last name.

Please enter a valid email address.

Occupation Please enter your occupation.

Affiliation Please enter any affiliation.

You have entered the maximum number of contributors

Conflicting interests

Do you have any conflicting interests? * Conflicting interests help

Yes No

More information * Please enter details of the conflict of interest or select 'No'.

Please tick the box to confirm you agree to our Terms of use. *

Please accept terms of use.

Please tick the box to confirm you agree that your name, comment and conflicts of interest (if accepted) will be visible on the website and your comment may be printed in the journal at the Editor’s discretion. *

Please confirm you agree that your details will be displayed.

Article contents

[no title]

Abstract

Article contents

[no title]

Abstract

Save article to Kindle

Save article to Dropbox

Save article to Google Drive

Reply to: Submit a response

Your details

You have entered the maximum number of contributors

Conflicting interests