21. 
Distances
and trees in dense subsets of Z^d (with
Akos Magyar) submitted 

20. 
Distance
graphs and sets of positive upper density in R^d
(with Akos Magyar) submitted 

19. 
Spherical
configurations over finite fields (with Akos
Magyar and Hans Parshall) to appear in Amer. J. Math. 

18. 
Product
of simplices and sets of positive upper
density in R^d (with
Akos Magyar) Math. Proc. Cambridge Philos. Soc. 165 (2018), no. 1, 2551 

17. 
Simplices
and sets of positive upper density in R^d
(with Lauren Huckaba and Akos
Magyar) Proc. Amer. Math. Soc. 145 (2017), no. 6, 2335–2347 

16. 
Polynomials
and
primes in generalized arithmetic progressions
(with Ernie Croot and Alex Rice) Int. Math. Res. Not. (2015), no. 15, 60216043 

15. 
A
quantitative result on Diophantine
approximation for intersective polynomials
(with Alex Rice) INTEGERS Volume 15A (2015), Proceedings of Integers 2013: The Erdös Centennial Conference 

14. 
A
purely combinatorial approach to simultaneous
polynomial recurrence modulo 1 (with Ernie Croot
and Alex Rice) Proc.
Amer. Math. Soc. 143 (2015), no. 8, 32313238


13. 
Improved
bounds
on
Sarkozy's
theorem
for quadratic polynomials (with Mariah Hamel and
Alex Rice) Int.
Math. Res. Notices (2013), no. 8, 17611782


12. 
A new proof of
Sarkozy's theorem Proc.
Amer. Math. Soc. 141 (2013), 22532264


11. 
Polynomial differences
in the primes (with
Alex Rice) Combinatorial
and Additive Number Theory (Proceedings of CANT 2011
and 2012), pp 129146. Springer Proc. in Math. &
Stat., 2014


10. 
Optimal polynomial
recurrence (with
Akos Magyar) Canad. J. Math. 65 (2013), no. 1, 171194
Here is
an exposition of the special case of squares: An optimal version of
Sarkozy's theorem 

9. 
Simultaneous polynomial
recurrence (with
Akos Magyar)
Bull. Lond. Math. Soc. 43 (2011), no. 4,
765785


8. 
Arithmetic structure in
sparse difference sets (with Mariah Hamel,
Katherine Thompson and Nathan Walters)
J. Number Theory 130 (2010), 15811589


7. 
Polynomial
configurations in difference sets (with Akos Magyar) J. Number Theory 129 (2009), 439450


6. 
Strongly singular
Radon transforms on the Heisenberg group and folding
singularities
(with Norberto Laghi)
Proc. Amer. Math. Soc. 136
(2008), no. 4, 12611272


5. 
Strongly
singular integrals along curves (with Norberto Laghi)
Pacific J. Math. 233 (2007),
no. 2, 403415


4. 
Strongly singular integral
operators associated to different quasinorms on the
Heisenberg group
(with Norberto Laghi)
Math. Res. Lett. 14
(2007), no. 5, 825838
Here
is a related determinant
calculation


3. 
Twoweight
estimates for singular and strongly singular
integral operators (with V. Kokilashvili and A.
Meskhi)
Acta Math. Hungar. 116 (2007),
no.12, 125


2. 
A class
of strongly singular Radon transforms on the
Heisenberg group Proc.
Edinb.
Math. Soc. (2) 50 (2007), 429457


1. 
Strongly singular
convolution operators on the Heisenberg group
Trans.
Amer. Math. Soc. 359
(2007), 44674488

Some Additional Expository Notes (these are very old, but
might still be useful to someone):