https://linkinghub.elsevier.com/retrieve/pii/S0167739X04001013
http://linkinghub.elsevier.com/retrieve/pii/S0097849397000617
https://linkinghub.elsevier.com/retrieve/pii/B9780444823229500943
http://linkinghub.elsevier.com/retrieve/pii/0956052195000372
https://linkinghub.elsevier.com/retrieve/pii/0097849394901678
https://linkinghub.elsevier.com/retrieve/pii/009784939190074R
http://www.springerlink.com/index/10.1007/978-3-642-76298-7_3
https://linkinghub.elsevier.com/retrieve/pii/B9780408029384500164
https://linkinghub.elsevier.com/retrieve/pii/B9780080507538501406
http://linkinghub.elsevier.com/retrieve/pii/009784939090070E
http://www.tandfonline.com/doi/abs/10.1080/00994480.1989.10748764
http://www.springerlink.com/index/10.1007/978-4-431-68093-2_22
http://www.springerlink.com/index/10.1007/978-3-642-83492-9_16
http://www.springerlink.com/index/10.1007/978-3-642-83492-9_15
http://www.springerlink.com/index/10.1007/978-3-642-71388-0_40
https://onlinelibrary.wiley.com/doi/10.1111/j.1467-8659.1985.tb00198.x
https://linkinghub.elsevier.com/retrieve/pii/0734189X85900969
http://www.springerlink.com/index/10.1007/978-3-642-84574-1_28