Twitter-icon.com has a great selection of twitter icons and buttons.
Site: economia-sniim.gob.mx (SNIIM - Sistema Nacional de Información de Mercados. Secretaría de Economía Precios de Frutas, Hortalizas, Vegetales, Carnes, Pescados, Pecuarios, Pesqueros)
Do you have a twitter account? If so it's important
to get as many people as possible to follow you.
Great follow me icon captures attention of the visitors
and brings more followers to your twitter account.
Choose great twitter icon for you website!