ERREFERENTZIAK

Artikuluak/Liburuak

• https://www.gipuzkoa.eus/documents/4004868/4007419/pelotaliburua.pdf/88e63661-4d83-41f6-9470-d62d4caf20d9
• https://books.google.es/books?hl=es&lr=&id=8GiBDwAAQBAJ&oi=fnd&pg=PA7&dq=material+reciclado+y+autoconstruido+pelota+vasca&ots=xBIhTINK4t&sig=HKTtbPbS8EatleEvPO3_jGj9xXk#v=onepage&q&f=false

Bideoak

• https://www.youtube.com/watch?v=jXdtBE0Ufmw
• https://www.youtube.com/watch?v=PW0p1GffcYQ

Blogak

• http://cramontellano.blogspot.com/2012/05/reciclamos-y-construimos-materiales.html