Interdisciplinary research often involves analyzing data obtained from different data sources with respect to the same subjects, objects, or experimental units. For example, global positioning systems ...

Cylindrical and spherical coordinates, double and triple integrals, line and surface integrals. Change of variables in multiple integrals; gradient, divergence, and ...

Many environmental sampling is often observed multiple spatially correlated variables at a given geographical location. For instance, multiple topsoil heavy metal concentrations, such as cadmium, zinc ...