Contentful.php SDK丢失

When requesting:

php composer.phar install contentful/contentful

as stated in the tutorial, the require function is suggested by Composer. However, when requesting:

php composer.phar require contentful/contentful

this is the feedback that is received:

 Problem 1
- The requested package contentful/contentful could not be found in any version, there may be a typo in the package name.

How do you install the SDK in this case?
Is this the only way to implement Contentful with PHP?

Contentful developer here.

The contentful/contentful package is currently only available as beta. To install a beta quality package just append :@beta to the command. The full command will look like this:

php composer.phar require contentful/contentful:@beta

While you could manually copy the SDK into your project, I'd advice strongly against it as you'll have to keep it up to date manually.