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

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

http://www.ece.rochester.edu/courses/ECE210/WikiOpAmpApps.pdf

http://www.analog.com/library/analogDialogue/archives/39-05/Web_Ch6_final_I.pdf

http://www.stanford.edu/class/ee122/Handouts/2-Op-Amp_Concepts.pdf

http://www.analog.com/library/analogDialogue/archives/39-05/op_amp_applications_handbook.html

http://www.allaboutcircuits.com/videos/82.html

http://www.allaboutcircuits.com/videos/81.html

http://www.facstaff.bucknell.edu/mastascu/elessonshtml/OpAmps/OpAmp1.html

http://books.google.com/books/about/Op_Amp_Applications_Handbook.html?id=dunqt1rt4sAC

http://www.indiabix.com/electronic-devices/op-amp-applications/

http://www.ee.nmt.edu/~rison/ee321_fall02/exams/exam1_soln.pdf

http://www.ecircuitcenter.com/circuits/opwien/opwien.htm

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

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

http://www.electronics-tutorials.ws/oscillator/rc_oscillator.html

http://en.wikibooks.org/wiki/Circuit_Idea/Simple_Op-amp_Summer_Design

http://users.ece.gatech.edu/mleach/ece3050/sp04/OpAmps01.pdf

http://uwf.edu/skamalasadan/final.pdf

http://www.allaboutcircuits.com/vol_3/chpt_8/11.html

http://courses.engr.illinois.edu/ece486/labs/lab1/analog_computer_manual.pdf

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

http://www.electronics.dit.ie/staff/ypanarin/Lecture%20Notes/DT021-4/6LogAntiLogAmplifiers.pdf

http://www.google.com/url?sa=t&rct=j&q=logarithm+circuit+with+op.&source=web&cd=10&ved=0CH4QFjAJ&url=http%3A%2F%2Ffaculty.ksu.edu.sa%2Falisaad%2FDocuments%2F313BMT%2F8.pptx&ei=M0ynT5rlBsTu-gaQyN3aAg&usg=AFQjCNHxL6rR6IHmlKrOXz_P1pUO1tkhHA