Fekel, Francis CHinkle, Kenneth HJoyce, Richard RWood, Peter RLebzelter, Thomas2015-12-070004-6256http://hdl.handle.net/1885/18948Infrared radial velocities have been used to compute first orbits of the M giants in three southern S-type symbiotic systems. Of the three, Hen 2-173 has the longest orbital period, 911 days, and also has a noncircular orbit with an eccentricity of 0.21.Keywords: Binaries: symbiotic; Infrared: stars; Stars: individual (AS 270, CL Scorpii, Henize 2-173); Stars: late-type200710.1086/5091332015-12-07