“Stationary” or “Stationery”—Which to use?

…the nucleus appear to a stationary observer as a "gluonic wall"…
…or when the vehicle becomes stationary.
…networks to exhibit a product-form stationary distribution.
Other dispensers are stationary and may have sophisticated features…
…negotiate and slammed into the stationary Juncadella.
…racing - which typically has stationary starts and race across the…
…charge and mass passing a stationary ion of charge and much…
…better and accurate firepower on stationary and moving targets alike.
…models having a so-called product-form stationary distribution" More recently, product-form solutions…
Stationary engineer

…such as torn edges, fancy stationery, sopping wet paper, or telegram
…Force Divisions (42–56), London: HM Stationery Office, 1935/Uckfield: Naval & Military…
…in the stamps and postal stationery of Finland for which he…
…made from bonded marble powder, stationery items and many classic CD…
…and 75th Divisions, London: HM Stationery Office, 1937/Uckfield: Naval & Military…
…an appropriate piece of company stationery in order to look inconspicuous…
(His Majesty's Stationery Office).
…Sampoerna A International Cyberworld, for stationery, accessories, clothing like Dunhill, Marlboro…
…the form of stamps, stamped stationery, precanceled stamps, postage meter imprints…
…printing among other work elegant stationery.

“Stationary” or “Stationery”