Melvin Simon & Assoc. in their comparative study of malls with lush and adequate plants vs. malls with minimal interior plants.
 CB Richard Ellis from their rent rate assessments in multiple markets and tenant appreciation studies. The percentage of lease rates varied from city to city with 20% being the average.
 Hotel in question has 1004 rooms facing three plant-filled atriums while 60% of its rooms face the exterior landscape. The atrium facing rooms achieve a 98% occupancy at a 20% lower room rate.
 Dr. Virginia Lohr of Washington State University in her study of the same staff in the same office doing the same work over six months. Plants were introduced after the first three months and dramatic increases in productivity were achieved.