Sanchez Font by LatinoType, and designed by Daniel Hernándex looks to be a really solid slab serif. Similar to Rockwell but with rounded forms.
You can download Regular and Italic for free: http://youworkforthem.com
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You can download Sinoz DSP Regular for free direct from Myfonts.
Source http://new.myfonts.com
Read MoreMore open source goodness from the folks at The League Of Movable Type.
Link http://typedesk.com/
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