These procedures have been developed over the past 25 years during practical field work for a variety of clients worldwide.
They are the result of my personal 'hands on' experience and experimentation in the field.
Many have been adopted by international organisations and many have been copied by other authors.
It is likely that others developed similar techniques at the same time as me, but I can confirm that, as all the procedures published here are my originals, they may be copied and used without fear of breach of copyright.