http://www.jhu.edu/signals/

http://en.wikibooks.org/wiki/Signals_and_Systems/Time_Domain_Analysis

http://web.eecs.umich.edu/~fessler/course/451/l/pdf/c2.pdf

http://www.ece.jhu.edu/~cooper/courses/214/signalsandsystemsnotes.pdf

http://www3.nd.edu/~mhaenggi/ee344-04/overview.html

http://en.wikipedia.org/wiki/LTI_system_theory

http://ocw.mit.edu/resources/res-6-007-signals-and-systems-spring-2011/lecture-notes/MITRES_6_007S11_lec05.pdf

http://maxim.ece.illinois.edu/teaching/fall08/lec3.pdf

http://www.ee.ucr.edu/~yhua/ee141/lecture2.pdf

http://web.eecs.umich.edu/~aey/eecs206/lectures/lti2.pdf

http://www.engineering.uiowa.edu/~systems/Exams/review.pdf

http://www.google.com/url?sa=t&rct=j&q=lti+systems+and+their+properties&source=web&cd=9&cad=rja&ved=0CGAQFjAI&url=http%3A%2F%2Fwww.le.ac.uk%2Feg%2Frqqg1%2FLectures%2FLecture3.ppt&ei=RNPmUNXoKZCa0QXlmIHQAQ&usg=AFQjCNHGOXLiAANthpS7O4S-Gya5Lf0UMQ&bvm=bv.1355534169,d.d2k

http://tintoretto.ucsd.edu/jorge/teaching/mae143a/lectures/3timedomainanalysis.pdf

http://www.cis.hut.fi/Opinnot/T-61.140/Luennot/Ch2.pdf

http://www.eecg.toronto.edu/~ahouse/mirror/engi7824/course_notes_7824_part7.pdf

http://cnx.org/content/m12177/latest/