[Jellby]

You need to embed both files, and to add both @font-face rules:

@font-face {
 font-family: 'DejaVuSans';
 src: url(Fonts/DejaVuSans.ttf);
 font-weight: normal;
 font-style: normal;
}

@font-face {
 font-family: 'DejaVuSans';
 src: url(Fonts/DejaVuSans-Oblique.ttf);
 font-weight: normal;
 font-style: italic;
}

Note the green parts are the same, the red parts are different.

Now it should be possible to have:

<p style="font-family: 'DejaVuSans'">Some <i>italic</i> words.</p>

(or with an external CSS instead of the "style" attribute)