https://en.wikipedia.org/wiki/Kernel_method

2019
https://towardsdatascience.com/kernel-secrets-in-machine-learning-pt-2-16266c3ac37c
https://towardsdatascience.com/kernel-secrets-in-machine-learning-2aab4c8a295f
https://towardsdatascience.com/support-vector-machines-soft-margin-formulation-and-kernel-trick-4c9729dc8efe
2006
http://agbs.kyb.tuebingen.mpg.de/lwk/