Dr. D. Scientific Consulting content is continually archived and preserved in the following schemes:

Portico Digital preservation:

*Dr. D. Scientific Consulting formely know as "Grupo Tchê Química" . We are updating our records. Thank you for understanding that it may take some time.

These schemes allow libraries to activate perpetual access rights when needed and offer assurance to libraries and publishers that their shared investments are protected and preserved for the future.

For further information about the Dr. D. Scientific Consulting digital preservation policy, please contact us at