## Systems-conjugate and focal points of fourth order nonselfadjoint differential equations

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- by Sui Sun Cheng PDF
- Trans. Amer. Math. Soc.
**223**(1976), 155-165 Request permission

## Abstract:

Systems-conjugate points have been studied by John Barrett in relation to selfadjoint fourth order differential equations of the form $({p_2}u'')'' + {p_0}u = 0$. This paper extends his results to the general nonselfadjoint fourth order differential equation via a system of second order equations.## References

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## Additional Information

- © Copyright 1976 American Mathematical Society
- Journal: Trans. Amer. Math. Soc.
**223**(1976), 155-165 - MSC: Primary 34C10
- DOI: https://doi.org/10.1090/S0002-9947-1976-0473334-3
- MathSciNet review: 0473334