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Vans Custom Culture - Design & submit your own design for a chance to win $25,000. Grab one of these sheets in-store : r/Vans
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![Two-Body Motion: Elements of Astromechanics. Peter van de Kamp. Freeman, San Francisco, 1964. viii + 147 pp. Illus. Paper, $2; cloth, $4. Two-Body Motion: Elements of Astromechanics. Peter van de Kamp. Freeman, San Francisco, 1964. viii + 147 pp. Illus. Paper, $2; cloth, $4.](https://www.science.org/cms/10.1126/science.149.3684.623.c/asset/e99db176-582d-4f01-8201-55a9da940dec/assets/science.149.3684.623.c.fp.png)
Two-Body Motion: Elements of Astromechanics. Peter van de Kamp. Freeman, San Francisco, 1964. viii + 147 pp. Illus. Paper, $2; cloth, $4.
![Positional Astronomy: Principles of Astrometry. With Special Emphasis on Long-Focus Astrometry. Peter van de Kamp. Freeman, San Francisco, 1967. 239 pp., illus. $6.50. Positional Astronomy: Principles of Astrometry. With Special Emphasis on Long-Focus Astrometry. Peter van de Kamp. Freeman, San Francisco, 1967. 239 pp., illus. $6.50.](https://www.science.org/cms/10.1126/science.156.3777.929.b/asset/617527bc-6589-42a7-94ee-2918a1140220/assets/science.156.3777.929.b.fp.png)