The <Related_URL> field specifies links to Internet sites that contain information related to the data, as well as related Internet sites such as project home pages, related data archives/servers, metadata extensions, online software packages, web mapping services, and calibration/validation data. The <Related_URL> field consists of:

• <URL_Content_Type> Describes the type of URL being referenced. The <URL_Content_Type> is selected from a list of controlled URL content type keywords and consists of:
• <Type> Describes the type resources being referenced by the URL. For example, <Type>GET DATA></Type>.
• <Subtype> Describes the subtype of the resource being referenced by the URL.
• <URL>is the URL to the resource associated with the data set.
• <Description> provides information about the resource defined by the <URL>.

<Related_URL>
    <URL_Content_Type>
      <Type>Related URL Type keyword</Type>
      <Subtype>Related URL Subtype keyword</Subtype>
    </URL_Content_Type>
    <URL>URL up to 600 characters</URL>
    <Description>Text</Description>
  </Related_URL>

• <Description> may contain multiple lines of text. Characters may be selected from the UTF-8 character set.

• The <Related_URL> field is highly recommended and may be repeated.
• The <URL_Content_Type> and <URL> fields are required.
• The <URL_Content_Type> subfields <Type> and <Subtype> must be selected from the set of URL Content Type keywords. <Subtype> is not required.
• The <URL> subfield may be repeated within the <Related_URL>.
• The <Description> subfield is recommended and unrepeatable.

<Related_URL>
    <URL_Content_Type>
      <Type>VIEW PROJECT HOME PAGE </Type>
    </URL_Content_Type>
    <URL>http://www.esipfed.org/</URL>
    <Description>Homepage of the Earth Science Information Partners (ESIP)</Description>
</Related_URL>

Example of a <Related_URL> with access to data:
<Related_URL>
   <URL_Content_Type>
      <Type> GET DATA </Type>
      <Subtype>GIOVANNI</Subtype>
    </URL_Content_Type>
    <URL> ftp://g0dup05u.ecs.nasa.gov/data/Giovanni/MODIS/GOCART/</URL>
    <Description>Access to data files </Description>
</Related_URL>

Example of a <Related_URL> with repeating <URL> subfields:

<Related_URL>
   <URL_Content_Type>
   <Type>GET DATA </Type>
   </URL_Content_Type>
   <URL>ftp://ftp.ncdc.noaa.gov/pub/data/paleo/paleocean/by_contributor/medina-elizalde2005/medina-elizalde2005.txt </URL>
   <URL>ftp://ftp.ncdc.noaa.gov/pub/data/paleo/paleocean/by_contributor/medina-elizalde2005/</URL>
   <Description>Access to data and documentation files </Description>
</Related_URL>