I need three sources books that describes how electrical eng

I need three sources books that describes how electrical engineering is important?
I have to do an essay but I need 3 free books (able to download free)
thank you so much

Solution

1)http://www.electrical4u.com

2)http://www.elec.canterbury.ac.nz/for/eceprospective.shtml

3)http://www.nzdl.org/gsdlmod?e=d-00000-00---off-0gtz--00-0----0-10-0---0---0direct-10---4-------0-1l--11-en-50---20-about---00-0-1-00-0--4----0-0-11-10-0utfZz-8-00&a=d&cl=CL1.3&d=HASH016d0f8759f065dba82c6bfa.3