Buen consejo

“The Portable Document Format (PDF) is a popular format to publish formatted text and documents. There are several different versions of it, some qualifying as an Open Standard, some certified by ISO and some encumbered by software patents. You might want to promote the versions that are Open Standards, because Open Standards guarantee interoperability, competition and choice”

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PDFreaders.org

Consigue un lector de PDFs libre; yo utilizo KPDF.