Attribute for <LINK ...>
TYPE = "MIME type"

TYPE gives an indication of the MIME type of the resource the tag links to. In practice TYPE is most useful when linking to an external CSS style sheet, in which case TYPE should have a value of text/css:

<LINK REL="stylesheet" TYPE="text/css" HREF="https://www.w3.org/StyleSheets/TR/W3C-REC">