Instead of passing in this parameters as a HTTP request header, you can also pass it in as an encoded URL parameter:
http://api.elsevier.com/content/search/scidir?query=[query]&httpAccept= application%2Fatom%2Bxml
By default, the AP will return 25 responses. You can get up to 100 responses by adding a 'count' parameter:
http://api.elsevier.com/content/search/scopus?query=heart&count=100
Beware, however, that higher counts negatively affect response time.
By default, the API will return standard bibliographic data for each record. A more complete set of data can be retrieved by using the 'VIEW' parameter:
http://api.elsevier.com/content/search/scopus?query=heart&view=COMPLETE
Requesting this view, especially in combination with requesting more than the standard 25 results, will negatively affect response time.
You can tailor the specific fields to be returned by using the 'fields' parameter. For example:
http://api.elsevier.com/content/search/scidir?query=heart&field=dc:title,dc:creator,prism:publicationName,prism:coverDate,dc:description,prism:doi
The available search fields are documented for ScienceDirect and Scopus.
By default, the API returns search results ordered by whatever the default sort order is on ScienceDirect/Scopus itself. However, it is also possible to force a sort order, e.g. descending (-) by date:
http://api.elsevier.com/content/search/scidir?query=decay&sort=-date