Frank J. Wilstach, comp. A Dictionary of Similes. 1916.
Stubborn
Stubborn as a mule.
—Anonymous
As stubborn as the will of kings.
—Ambrose Bierce
As stubborn as Muirkirk iron.
—James Hogg
Stubborn as a stone.
—Victor Hugo
Stubborn people are like reproaches, and we have a right to laugh at them.
—Victor Hugo
Stubborn as the Rocky Mountains.
—Richard Le Gallienne
Stubborn as an elephant’s leg, no bending in her.
—William Rowley
More stubborn-hard than hammer’d iron.
—William Shakespeare