AnalyticVolume elem = new AnalyticVolume();
av.addAnalyticVolume(elem);
return elem;
} else if (elementName.equals(SpatialConstants.sampledVolume)) {
SampledFieldGeometry sfg = (SampledFieldGeometry) listOf.getParentSBMLObject();
SampledVolume elem = new SampledVolume();
sfg.addSampledVolume(elem);
return elem;
} else if (elementName.equals(SpatialConstants.csgPrimitive)) {
CSGSetOperator csgso = (CSGSetOperator) listOf.getParentSBMLObject();
CSGPrimitive elem = new CSGPrimitive();