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

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

http://www-personal.umich.edu/~chadjo/research/embasic/node1.htmlhttp://math-physics.tumblr.com/

http://mathworld.wolfram.com/Curl.html

http://www-cm.math.uiuc.edu/Syllabi?q=node/23

http://www.vias.org/calculus/13_vector_calculus_06_04.html

http://www.solitaryroad.com/c606.html

Vector Laplacian

Laplacian

http://www.eaeeie.org/theiere/curvilinear/FieldOperators.htm

http://www.ehow.com/info_12010884_definition-curl-gradient-divergence.html

http://www.euclideanspace.com/maths/differential/vectorcalculus/grad/index.htm

http://hyperphysics.phy-astr.gsu.edu/hbase/vecal.html

Vector Laplacian

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

http://mysite.du.edu/~jcalvert/math/eucltens.htm

http://er.jsc.nasa.gov/seh/l.html

http://www.aishack.in/2010/08/image-convolution-examples/

http://www.cmbi.ru.nl/molden/laplacian.html

http://mipav.cit.nih.gov/documentation/HTML%20Algorithms/Edge_Detection_Zero_X.html

**Lagrangian**

http://orlaningsolidstate.blogspot.com/2010_03_01_archive.html

http://www.worldforge.org/project/newsletters/May2002/LMMS_index

http://stochasticandlagrangian.blogspot.com/2011/02/on-lagranges-ubiquiti-in-modern-physics.html

Sexy modern notation hides the immense manipulations going on beneath.

Always ask

…What lies beneath?