Argentinosaurus

Argentinosaurus was a titanosaurid sauropod dinosaur. It was an enormous, long-necked, long-tailed, quadrupedal, plant-eater from Argentina, South America during the Cretaceous period.
"Argentinosaurus" meaning "Argentina lizard", was named by paleontologists Coria &amp; José Bonaparte in 1993. It is known from fossilized back vertebrae, tibia, ribs and sacrum, found in Neuquén Province. It may be the largest dinosaur, but its remains are so incomplete that palaeontologists prefer to use "Saltasaurus" for their calculations. An accurate estimate was got for the much more complete sub-adult "Dreadnoughtus".
Rough estimates.
The following shows the disagreement on estimates of size: