That's the english abstract of Etchamendy's thesis:
"Since the 19th century, the basque language has been renowned as the sole
ancient language of Europe with non-european origins: a language without
parentage, an orphan language or the remnant of an extinct family of
languages. Its vocabulary would be largely borrowed from other sources,
especially from latin and roman, but its grammar along with a core cluster
of words, would be specific. However, no exhaustive study comparing the
basque language with indo-european languages has been carried out. In our
opinion its description is incomplete and sometimes equivocal. Our thesis is
an essay analysing euskera using the comparative method between basque and
reconstructed indo-european grammar (tome I) as well as the basic elements,
around 4000 of them (tome II). It appears that the supposed specificities of
the basque language (ergative syntax, nominal predicate, absence of gender,
morphology, etc.) were caracteristics of indo-european before its
hypotetical division into groups, and its archaic aspects are beginning to
emerge (Martinet, Vaillant, Laroche, C.Tcheckoff). Finally, the core lexical
cluster proper to euskera --if we take it to mean without common roots--has
not surface so far."
You can read more about Etchamendy 's work (in french) on his web site:
http://www.etchamendy.com/