How to use crossref.org API URL, /works/{doi}/transform, for DOI content negotiation?

crossref.org API URL /works/{doi}/transform allows you to use the DOI Content Negotiation service to request a particular representation of metadata associated with a given DOI.

DOI Content Negotiation is done by a HTTPS request with an explicit header called "Accept" to specify the MIME type identifying a particular representation. Here is the syntax of the HTTPS request on DOI Content Negotiation:

GET https://api.crossref.org/works/{doi}/transform HTTP/1.1
Accept: {mime}

DOI Content Negotiation supports the following MIME types for different representations:

MIME Type                               Representation
--------------------------------------- ------------------------
application/rdf+xml                     RDF XML
application/vnd.citationstyles.csl+json Citeproc JSON
application/vnd.crossref.unixref+xml    Crossref Unixref XML
application/vnd.crossref.unixsd+xml     Crossref UNIXSD XML
application/x-bibtex                    BibTeX
application/x-research-info-systems     RIS
text/turtle                             RDF Turtle
text/x-bibliography                     Formatted text citation

Here is an example of how to use the DOI Content Negotiation service to get the formatted text citation string of a given DOI:

fyicenter$ curl -H "Accept: text/x-bibliography" \
  https://api.crossref.org/works/10.1037/0003-066x.59.1.29/transform 

Ray, O. (2004). How the Mind Hurts and Heals the Body. 
American Psychologist, 59(1), 29–40. https://doi.org/10.1037/0003-066x.59.1.29

Here is another example of how to use the DOI Content Negotiation service to get the Citeproc JSON format of a given DOI:

fyicenter$ curl -LH "Accept: application/vnd.citationstyles.csl+json" \
  https://api.crossref.org/works/10.1037/0003-066x.59.1.29/transform

{
  "DOI": "10.1126/science.169.3946.635",
  "ISSN": [
    "0036-8075",
    "1095-9203"
  ],
  "URL": "http://dx.doi.org/10.1126/science.169.3946.635",
  "alternative-id": [
    "10.1126/science.169.3946.635"
  ],
  "author": [
    {
      "affiliation": [
        {
          "name": "University of Pittsburgh, Mellon Institute of Carnegie-Mellon University"
        }
      ],
      "family": "Frank",
      "given": "Henry S.",
      "sequence": "first"
    }
  ],
  "container-title": "Science",
  "container-title-short": "Science",
  "content-domain": {
    "crossmark-restriction": false,
    "domain": []
  },
  "created": {
    "date-parts": [
      [
        2006,
        10,
        5
      ]
    ],
    "date-time": "2006-10-05T12:56:56Z",
    "timestamp": 1160053016000
  },
...

⇒ crossref.org API - /works/{doi}/transform/{mime}

⇐ crossref.org API - /funders for Funders

⇑ Crossref.org DOI Database

⇑⇑ DOI - Frequently Asked Questions